WASHINGTON — The Obama administration made good on an ultimatum Monday and withdrew its cooperation with Russia over Syria, while Moscow suspended a key nuclear weapons treaty it had signed with Washington more than a decade ago.

With the two governments signaling their anger at each other, U.S.-Russia ties hit one of their lowest points since the 1991 collapse of the Soviet Union.

Exasperated over relentless Russian and Syrian airstrikes on the battered city of Aleppo, Washington announced it was breaking off bilateral talks with Russia over Syria’s fate and canceling plans to share military intelligence and operations-related information with Moscow.

“This is not a decision that was taken lightly,” State Department spokesman John Kirby said in a statement.

The decision came after continuous negotiations, including near-daily telephone conversations between Secretary of State John F. Kerry and Russian Foreign Minister Sergei Lavrov, aimed at reducing violence and opening up routes for desperately needed food and medicine for besieged enclaves. They last spoke Saturday, and the Obama administration’s decision was conveyed to Russian negotiators in Geneva.

“Unfortunately, Russia failed to live up to its own commitments,” Kirby said, “and was also either unwilling or unable to ensure Syrian regime adherence to the arrangements to which Moscow agreed.”

Instead, the U.S. alleges, Russia and its ally, the government of Syrian President Bashar Assad, used the time to pound rebel-held portions of Aleppo and numerous civilian neighborhoods with barrel bombs and other indiscriminate attacks. Hundreds of people have been killed in the last week.

Russia had agreed to a cease-fire last month, but that fell apart quickly. Russia argues that the United States has failed in its commitment to separate the moderate rebel groups it supports from more radical factions such as the Syrian branch of al-Qaida.

Kirby said the United States will withdraw a team that had been dispatched to open a so-called joint implementation center, in which Russian and American armed forces were going to join efforts to fight Islamic State and other jihadi groups.

Also Monday, Russian President Vladimir Putin signed a decree suspending his country’s participation in a treaty with the U.S. designed to eliminate nuclear weapons.

Putin cited “a threat to strategic stability as a result of USA’s unfriendly acts toward Russia.” This was a reference to a deepening diplomatic spat between the Kremlin and the White House over Syria, as well as tensions and sanctions that followed Russia’s 2014 takeover of Crimea and its support to separatists in eastern Ukraine.

It is the latest action by Russia that serves to unwind the nuclear cooperation and weapons treaties that have governed the relationship between the U.S. and Russia in the years after the Soviet dissolution.

The nuclear deal suspended Monday was to process 34 tons of weapons-grade plutonium — enough to make 17,000 nuclear warheads; it was signed in 2000 by the outgoing administration of President Bill Clinton and Putin’s first government. Expanded in 2006 and 2010, it was among the last strategic accords that put an end to the arms race and were enforced despite the ups and downs of U.S.-Russia relations after the 1991 Soviet collapse.

Putin’s decree stipulates that Moscow will resume its participation in the accord only if the U.S. fulfills a list of demands, many of which run contrary to security policies the U.S. has pursued for decades. The White House would have to lift all anti-Russian sanctions, “compensate” Russia for the sanctions-related losses and reduce the U.S. military presence in Eastern Europe to pre-2000 levels. In 2015, NATO opened command points in six Eastern European nations allowing a swift deployment of troops and arms.

The Obama administration said it “regretted” Putin’s action and accused Russia of being the main destabilizing power in the region.

In the decree, Moscow also claims that Washington is training ultranationalist militants in Ukraine and “openly stands up to protect economic crimes” in Russia. It also wants the U.S. to remove personal sanctions and travel bans against Russian officials — a targeted move that hurt some of Putin’s oldest and closest allies whose family members live or study in Western Europe or the United States.

“The decision we made is a signal to Washington,” Lavrov said in a statement posted on his ministry’s website. “Attempts to talk to Russia from the position of power — to use the language of sanctions and ultimatums, and at the same time, to continue a selective partnership with our country only in the areas that are beneficial to the U.S. — are not going to work.”

Although the two dramatic announcements — the break over Syria and the suspension of the nuclear treaty — occurred within hours of each other, U.S. officials cautioned against seeing the events as tit-for-tat.

The U.S. said it would continue to participate in multilateral talks over Syria, aimed at achieving a cessation of hostilities and the delivery of aid, and would communicate with Russia regarding airstrikes to avoid collisions.

Last week, when it first threatened to suspend Syria talks with Russia, Washington said it would consider other options, including additional financial sanctions or even military operations.

State Department spokeswoman Elizabeth Trudeau would not pinpoint what the final straw was that forced the administration decision, although there were numerous reports over the weekend of Russian-backed Syrian forces bombing hospitals and using chemical weapons.

“This is a grave decision,” she said. “We are very much considering the next step. … Clearly (the Russians) have not pulled back. Clearly they have not ceased their attacks. Nor has the regime. … We came to a point with Russia where we weren’t (pursuing) the same goal.”

Putin’s decree, meanwhile, also calls on the U.S. to provide a detailed plan for the destruction of the 34 tons of plutonium.

Enriched, weapons-grade plutonium or uranium can be detonated to start a spontaneous fission that leads to a nuclear explosion, and the U.S.-Russian deal prescribed the burning of the fuel in remodeled reactors that could be monitored by both sides and international inspectors.

In 2015, Russia started burning the plutonium at a nuclear power station in the Urals region. A similar facility in South Carolina remains unfinished because of high costs.

“We fulfilled our duties, we built the facility. Our American partners did not,” Putin said in televised remarks.

Instead, Putin said, the U.S. opted to mix the plutonium with other, nonradioactive materials and store the mix.

“It means that they are retaining the so-called reverse potential, i.e. (the fuel) can yet again be retrieved, reprocessed and turned into weapons-grade plutonium. That’s not what we agreed to.”

Times staff writer Wilkinson reported from Washington and special correspondent Mirovalev from Moscow.

 ©2016 Tribune Co.

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 Distributed by Tribune Content Agency, LLC.</s>MOSCOW, Oct 3 (Reuters) - Russian President Vladimir Putin on Monday suspended a treaty with Washington on cleaning up weapons-grade plutonium, signalling he is willing to use nuclear disarmament as a new bargaining chip in disputes with the United States over Ukraine and Syria.

Starting in the last years of the Cold War, Russia and the United States signed a series of accords to reduce the size of their nuclear arsenals, agreements that have so far survived intact despite a souring of U.S.-Russian relations under Putin.

But on Monday, Putin issued a decree suspending an agreement, concluded in 2000, which bound the two sides to dispose of surplus plutonium originally intended for use in nuclear weapons.

The Kremlin said it was taking that action in response to unfriendly acts by Washington.
• Pact is on disposing of surplus plutonium
• Disarmament now drawn in to U.S.-Russia rows

The plutonium accord is not the cornerstone of post Cold War U.S.-Russia disarmament, and the practical implications from the suspension will be limited. But the suspension, and the linkage to disagreements on other issues, carries powerful symbolism.

"Putin's decree could signal that other nuclear disarmament cooperation deals between the United States and Russia are at risk of being undermined," Stratfor, a U.S.-based consultancy, said in a commentary.

"The decision is likely an attempt to convey to Washington the price of cutting off dialogue on Syria and other issues."

U.S. Secretary of State John Kerry last week warned that Washington could halt diplomacy with Russia over the conflict in Syria unless Russia took immediate steps to stop the violence there.

Western diplomats say an end to the Syria talks would leave Moscow without a way to disentangle itself from its military operation in Syria. The operation was intended to last a few months but has now just entered its second year.

As well as issuing the decree ordering the suspension of the plutonium cleanup deal, Putin submitted a draft law on the suspension to parliament.

That draft linked the suspension to a laundry list of Russian grievances towards the United States.

It said conditions for resuming work under the plutonium deal included Washington lifting sanctions imposed on Russia over its role in the Ukraine conflict, paying compensation to Moscow for the sanctions, and reducing the U.S. military presence in eastern Europe to the levels they were 16 years ago.

Any of those steps would involve a complete U-turn in long-standing U.S. policy.

"The Obama administration has done everything in its power to destroy the atmosphere of trust which could have encouraged cooperation," the Russian foreign ministry said in a statement on the treaty's suspension.

"The step Russia has been forced to take is not intended to worsen relations with the United States. We want Washington to understand that you cannot, with one hand, introduce sanctions against us where it can be done fairly painlessly for the Americans, and with the other hand continue selective cooperation in areas where it suits them."

The 2010 agreement, signed by Russian Foreign Minister Sergei Lavrov and then-U.S. Secretary of State Hillary Clinton, called on each side to dispose of 34 tons of plutonium by burning it in nuclear reactors.

Clinton said at the time that there was enough of the material to make almost 17,000 nuclear weapons. Both sides back then viewed the deal as a sign of increased cooperation between the two former Cold War adversaries.

Russian officials alleged on Monday that Washington had failed to honour its side of the agreement. The Kremlin decree stated that, despite the suspension, Russia's surplus weapons-grade plutonium would not be put to military use.</s>MOSCOW (Reuters) - Russian President Vladimir Putin on Monday suspended a treaty with Washington on cleaning up weapons-grade plutonium, signaling he is willing to use nuclear disarmament as a new bargaining chip in disputes with the United States over Ukraine and Syria.

Russian President Vladimir Putin attends an awarding ceremony at the Kremlin in Moscow, Russia, September 22, 2016. REUTERS/Ivan Sekretarev

Starting in the last years of the Cold War, Russia and the United States signed a series of accords to reduce the size of their nuclear arsenals, agreements that have so far survived intact despite a souring of U.S.-Russian relations under Putin.

But on Monday, Putin issued a decree suspending an agreement, concluded in 2000, which bound the two sides to dispose of surplus plutonium originally intended for use in nuclear weapons.

The Kremlin said it was taking that action in response to unfriendly acts by Washington. It made the announcement shortly before Washington said it was suspending talks with Russia on trying to end the violence in Syria.

The plutonium accord is not the cornerstone of post-Cold War U.S.-Russia disarmament, and the practical implications from the suspension will be limited. But the suspension, and the linkage to disagreements on other issues, carries powerful symbolism.

“Putin’s decree could signal that other nuclear disarmament cooperation deals between the United States and Russia are at risk of being undermined,” Stratfor, a U.S.-based consultancy, said in a commentary.

“The decision is likely an attempt to convey to Washington the price of cutting off dialogue on Syria and other issues.”

U.S. State Department spokesman John Kirby said in a statement on Monday that bilateral contacts with Moscow over Syria were being suspended. Kirby said Russia had failed to live up to its commitments under a ceasefire agreement.

Western diplomats say an end to the Syria talks leaves Moscow free to pursue its military operation in support of Syrian President Bashar al-Assad, but without a way to disentangle itself from a conflict which shows no sign of ending.

Russia and the United States are also at loggerheads over Ukraine. Washington, along with Europe, imposed sanctions on Russia after it annexed Ukraine’s Crimea region in 2014 and backed pro-Moscow rebels in eastern Ukraine.

LIST OF GRIEVANCES

Putin submitted a draft law to parliament setting out under what conditions work under the plutonium accord could be resumed. Those conditions were a laundry list of Russian grievances towards the United States.

They included Washington lifting the sanctions imposed on Russia over Ukraine, paying compensation to Moscow for the sanctions, and reducing the U.S. military presence in NATO member state in eastern Europe to the levels they were 16 years ago.

Any of those steps would involve a complete U-turn in long-standing U.S. policy.

“The Obama administration has done everything in its power to destroy the atmosphere of trust which could have encouraged cooperation,” the Russian foreign ministry said in a statement on the treaty’s suspension.

“The step Russia has been forced to take is not intended to worsen relations with the United States. We want Washington to understand that you cannot, with one hand, introduce sanctions against us where it can be done fairly painlessly for the Americans, and with the other hand continue selective cooperation in areas where it suits them.”

The 2010 agreement, signed by Russian Foreign Minister Sergei Lavrov and then-U.S. Secretary of State Hillary Clinton, called on each side to dispose of 34 tonnes of plutonium by burning it in nuclear reactors.

Clinton said at the time that there was enough of the material to make almost 17,000 nuclear weapons. Both sides back then viewed the deal as a sign of increased cooperation between the two former Cold War adversaries.

Russian officials alleged on Monday that Washington had failed to honor its side of the agreement. The Kremlin decree stated that, despite the suspension, Russia’s surplus weapons-grade plutonium would not be put to military use.</s>MOSCOW -- Russian President Vladimir Putin, saying that relations with the United States have deteriorated into a "radically changed environment" of threat and instability, on Monday withdrew his country from a plutonium-disposal treaty that was one of the framework nuclear-disarmament deals of the early post-Cold War period.

The treaty on the disposal of plutonium, the material used in some nuclear weapons, was concluded in 2000.

It required Russia and the United States to destroy military stockpiles of plutonium, a deal presented as another encouraging step away from nuclear doomsday and an insurance policy against the materials falling into the hands of terrorists or rogue states.

The deal has no bearing on the numbers of nuclear weapons deployed by Russia or the United States. Instead, it concerns 34 tons of plutonium in storage in each country that might go into a future arsenal, none of which has yet undergone verifiable disposal.

The Kremlin had signaled previously that it planned to cut back on mutual efforts with the United States to secure nuclear material on Russian territory.

Times have changed, Putin wrote in the decree signed Monday.

"The threat to strategic stability posed by the hostile actions of the U.S. against Russia, and the inability of the U.S. to deliver on the obligation to dispose of excessive weapons plutonium under international treaties," forced Russia's hand, he wrote.

Josh Earnest, the White House press secretary, said the administration was disappointed by the Russian decision since "both leaders in Russia and the United States have made nonproliferation a priority."

"We've also been quite disappointed by a range of Russian decisions both in Syria and inside of Ukraine," Earnest said, adding that the decision on the plutonium deal was part of a problematic pattern.

Russia will withdraw from the original pact and subsequent amendments, Putin's decree says, meaning the country will no longer be treaty-bound to destroy its plutonium stockpiles. But the decree also offers an assurance, backed by no bilateral agreement, that the plutonium will not be used for military purposes.

"These agreements were designed to limit and circumscribe the future chances of getting back into a competition over nuclear arms," James Collins, an associate at the Carnegie Endowment for International Peace, said in a telephone interview. "It was an important step in defusing the strategic nuclear arms race."

Collins, who was the United States' ambassador to Russia when the agreement was signed, called the abrogation a "strange move," given the extraordinary danger, not least to Russians, should plutonium fall into terrorist hands. He added that it was "in my understanding the first time they have withdrawn from a specific nuclear agreement," highlighting the slide in relations lately.

Russia and the United States had reaffirmed the plutonium-disposal agreement in 2009, as President Barack Obama pursued the "reset" policy with Dmitry Medvedev, then the Russian president.

Russia had viewed the agreement as rendering disarmament irreversible by destroying the fissile materials accumulated during the Cold War. In this light, the Russians had interpreted the treaty as requiring that the plutonium be irreversibly transformed into nonexplosive materials by using it in civilian nuclear power plants as mixed oxide fuel. Russia is pressing ahead with that.

But glitches and cost overruns in the mixed oxide fuel plant at Savannah River, S.C., delayed the U.S. program. This year, Obama proposed canceling the program in the 2017 budget and instead sending the plutonium for long-term storage at a nuclear waste site in Carlsbad, N.M.

The State Department has said the move complies with the treaty, but the Russians have said it does not, as Putin reaffirmed on Monday.

As ties with the West have frayed under Putin, analysts in Moscow have floated the prospect of a Russian pullback from an array of disarmament agreements dating from a period of greater friendliness. Two years ago, for example, the Obama administration accused Russia of violating another bedrock security agreement by testing a prohibited ground-launched cruise missile.

In order to resume cooperation on plutonium, the Kremlin first wants the removal of all economic sanctions and compensation for the damage they have caused; the repeal of the Magnitsky Act, which allows Americans to freeze the assets of Russian officials thought to have been involved with human-rights violations; and reductions in the U.S. military presence in countries that joined NATO after Sept. 1, 2000.</s>MOSCOW — President Vladimir Putin on Monday suspended a Russia-U.S. deal on the disposal of weapons-grade plutonium, a move that comes amid escalating tensions over Syria between Moscow and Washington.

Putin's decree released by the Kremlin cited Washington's "unfriendly actions" and the United States' inability to fulfill its obligations under the 2000 deal as reasons for the move.

However, the decree says that the weapons-grade plutonium that has fallen under the agreement will be kept away from weapons programs.

Under the agreement, which was expanded in 2006 and 2010, Russia and the U.S. each were to dispose of 34 metric tons of weapons-grade plutonium, enough material for about 17,000 nuclear warheads.

When it was signed, the deal was touted as an example of successful U.S.-Russian cooperation on nuclear non-proliferation.

Russia said last year it had started up a plant that produces mixed-oxide commercial nuclear reactor fuel known as MOX from weapons-grade plutonium. Meanwhile, the construction of a similar U.S. plant in South Carolina has been years behind schedule and billions of dollars over budget.

The U.S. administration wants to cancel the Savannah River Site's MOX project and use an alternative method for disposing of excess plutonium.

Putin pointed to the stalled plant earlier this year to accuse the U.S. of failing to meet its end of the deal. He also argued that the policy change would give the U.S. "return potential," or a chance to recycle the material back into the weapons-grade plutonium.

Commenting on Putin's move, the Russian Foreign Ministry said Monday that the U.S. has "done all it could to destroy the atmosphere encouraging cooperation." It cited U.S. sanctions against Russia over the Ukrainian crisis and the deployment of NATO forces near Russian borders as examples.

"We would like to bring Washington back to understanding that it can't introduce sanctions against us in areas where it's quite painless for the Americans, and at the same time continue selective cooperation in areas it sees as advantageous," it said.

A strain in U.S.-Russian ties escalated in recent weeks followed the collapse of a truce in Syria and the Syrian army's massive onslaught in Aleppo under the cover of Russian warplanes.

The Russian Foreign Ministry said Moscow would be ready to restore the plutonium agreement if the U.S. takes Russian concerns into account.</s>President Vladimir Putin has suspended a Russia-U.S. deal on the disposal of weapons-grade plutonium.

A decree Putin issued Monday cited “unfriendly actions” and the United States’ inability to fulfil its obligations under the 2000 deal as reasons for the move.

Under the agreement, Russia and the U.S. each were to dispose of 34 metric tons of weapons-grade plutonium, enough material for about 17,000 nuclear warheads.

When it was signed, the deal was touted as an example of successful U.S.-Russian co-operation on nuclear non-proliferation. However, Putin has accused the U.S. of failing to meet its end of the deal.

Construction of a U.S. plant where weapons-grade plutonium would be turned into commercial nuclear reactor fuel has been years behind schedule and billions of dollars over budget.</s>Workers load uranium-plutonium mixed oxide (MOX) civilian fuel made from American military plutonium on a boat heading to the US, at the port in Cherbourg, northern France, on March 22, 2005 (AFP Photo/Mychele Daniau)

Moscow (AFP) - Russian President Vladimir Putin on Monday ordered a halt to an agreement with the United States on plutonium disposal, citing Washington's "unfriendly actions".

The deal, signed in 2000, was meant to allow both nuclear powers to dispose of weapons-grade plutonium from their defence programmes, a move seen as a key step in the disarmament process.

The two countries recommitted to the deal in 2010.

The Kremlin indicated Monday that it would stick to the agreement if Washington lifts sanctions and ends other policies seen as unfriendly to Moscow.

Putin charged earlier this year that the United States was not honouring the deal by disposing of plutonium in a way that allowed it to retain its defence capabilities.

The suspension is symbolic of the breakdown in nuclear nonproliferation cooperation, an expert said.

The decree published Monday states that Russia is pulling out of the agreement "due to a drastic change in circumstances, the appearance of a threat to strategic stability due to unfriendly actions of the United States toward Russia".

It claimed that Washington was "unable" to carry out the terms of the agreement and that Moscow "must take urgent measures to defend Russian security".

Putin's spokesman Dmitry Peskov told journalists that Washington has not honoured the agreement and "Russia no longer thinks it possible to carry out the conditions of the agreement alone" due to "general tension" between the two countries.

"It's a symbolic gesture that demonstrates that the sides no longer cooperate in this sphere," said independent military expert Alexander Golts, adding that it was not the first agreement to be suspended in the non-proliferation sphere.

A bill submitted by Putin to parliament, which asked lawmakers to support the agreement's suspension, indicated that some quid pro quo could still keep the deal alive.

The bill said that the agreement could be reinstated if Washington moves US forces out of countries that became NATO members after 2000, ends "all sanctions" and compensates Moscow for the financial losses resulting from them.

Lawmakers can vote on the bill as early as Wednesday, when the State Duma convenes for the first time since being elected last month in a vote that saw the ruling United Russia party sweep some three quarters of the seats.

The US-Russian Plutonium Management and Disposition Agreement obliges Moscow and Washington to dispose of no less than 34 tonnes of weapon-grade plutonium by irradiating it or transforming it into so-called MOX (mixed oxide) fuel.

The building of a MOX fuel reprocessing plant was opposed in the United States in the wake of the 2011 Fukushima nuclear disaster in Japan over safety fears and high cost of the project, which is already billions of dollars over budget.

US energy officials have pushed for using another method of disposal, calling for plutonium to be mixed with other substances and stored underground, but Moscow argues that any method to dilute plutonium is reversable.

Russia is locked in its worst standoff with the West since the Cold War over its 2014 annexation of Crimea and the conflict in Ukraine.</s>Russian president Vladimir Putin on Monday suspended an agreement with the US for disposal of weapons-grade plutonium because of “unfriendly” acts by Washington, the Kremlin said.

A Kremlin spokesman said Mr Putin had signed a decree suspending the 2010 agreement under which each side committed to destroying tonnes of weapons-grade material because Washington had not been implementing it and because of current tensions in relations.

Russia wants the US to cancel all sanctions and pay compensation for the damage they have caused if Moscow is to resume the agreement, according to a draft law submitted by Mr Putin on Monday.

Russia also named as conditions for resuming the plutonium accord that Washington repeal its “Magnitsky Act” and that it reduce its military infrastructure and troops in countries that joined the Nato military alliance after September 1st, 2000, according to a copy of the draft law posted on the website of Russia’s lower house of parliament.

The two former Cold War adversaries are at loggerheads over a raft of issues including Ukraine, where Russia annexed Crimea in 2014 and is supporting pro-Moscow separatists, and the conflict in Syria.

The plutonium-disposal deal, signed in 2000 but which did not come into force until 2010, was being suspended due to “the emergence of a threat to strategic stability and as a result of unfriendly actions by the United States of America towards the Russian Federation”, the preamble to the decree said.

It also said that Washington had failed “to ensure the implementation of its obligations to utilise surplus weapons-grade plutonium”.

The 2010 agreement, signed by Russian foreign minister Sergei Lavrov and then-US secretary of state Hillary Clinton, called on each side to dispose of 34 tonnes of plutonium by burning in nuclear reactors.

Mrs Clinton said at the time that that was enough material to make almost 17,000 nuclear weapons. Both sides then viewed the deal as a sign of increased co-operation between the two former adversaries towards a joint goal of nuclear non-proliferation.

“For quite a long time, Russia had been implementing it [the agreement] unilaterally,” Kremlin spokesman Dmitry Peskov told a conference call with journalists on Monday.

“Now, taking into account this tension [in relations] in general . . . the Russian side considers it impossible for the current state of things to last any longer.”

Washington led a campaign to impose Western economic sanctions on Russia for its role in the Ukraine crisis.

Relations soured further last year when Russia deployed its warplanes to an air base in Syria to provide support for Syrian president Bashar al-Assad‘s troops fighting rebels.

The rift has widened in recent weeks, with Moscow accusing Washington of not delivering on its promise to separate units of moderate Syrian opposition from “terrorists”.

Huge cost overruns have also long been another threat to the project originally estimated at a total of $5.7 billion (€5.07bn).</s>Russian President Vladimir Putin has suspended a post-Cold War deal with the US on disposal of plutonium from decommissioned nuclear warheads.

Putin signed a decree on Monday to suspend an agreement with the United States on disposing of weapons-grade plutonium, in a further sign of worsening ties between the former Cold War foes.

The decision was explained by “the hostile actions of the US” against Russia along with Washington’s failure to abide by the terms of the deal.

A decree signed by Russian President Vladimir Putin cites “the radical change in the environment, a threat to strategic stability posed by the hostile actions of the US against Russia, and the inability of the US to deliver on the obligation to dispose of excessive weapons plutonium under international treaties, as well as the need to take swift action to defend Russian security” as justification for suspending the deal.

While Russia suspended the plutonium reprocessing deal, it stressed that the Russian fissile material, which was subject to it, would not be used for any military purpose, be it production of new weapons or research.

The development was not entirely surprising, since Russia earlier expressed its dissatisfaction with how the US wants to handle plutonium disposal.

Washington decided it would be cheaper to mix nuclear materials with special additives. Russia insisted that the US was violating the terms of the deal, which required it to use a nuclear reactor to transmute plutonium. Unlike the mixing technology, the latter method makes the process irreversible.

The treaty between the US and Russia, which regulates how the two countries are to dispose of plutonium from nuclear warheads decommissioned as part of the parallel reduction of the two countries’ Cold War arsenals, was signed in 2000. Each country was required to dispose of over 34 tons of fissile material by turning it into so-called MOX fuel and burning it in nuclear reactors.

However, costs for building a facility at the Savannah River Site in South Carolina, where the US was supposed to fabricate MOX fuel from its plutonium, spiraled out of control. Under the Obama administration, the US decided that it would instead use the cheaper reversible process, arguing that it was in line with the spirit of the deal with Russia.

Russia expressed its concerns over the unilateral move in April, shortly after a nuclear security summit held in the US.

“We signed an agreement that the plutonium will be processed in a certain way, for which facilities would be purpose-built,” Putin said at the time. “We have met our commitments, and constructed the necessary facilities. The US has not.”

The US rejected the criticism from Russia. The “new US method would not require renegotiation of the agreement,” US State Department spokesperson Jennifer Bavisotto said.</s>Russian President Vladimir Putin on Monday ordered a halt to an agreement with the United States on weapons-grade plutonium disposal in retaliation for Washington’s “unfriendly actions” amid a wider standoff with the West.

The deal, signed in 2000, was meant to allow both nuclear powers to dispose of plutonium from their defense programmes, a move seen as a key step in the disarmament process.

The two countries recommitted to the agreement in 2010.

Foreign minister Sergei Lavrov said the move was a “necessary” response to hostile steps from the US, including sanctions over the Ukraine crisis and the bolstering of NATO’s forces near Russia’s border.

“The decision that has been taken by us is a signal to Washington,” Lavrov said in a statement.

“It will not work out if they try to talk to Russia from a position of strength with the language of sanctions and ultimatums, but still want to maintain selective cooperation when it benefits the US.”

The suspension is symbolic of the breakdown in nuclear non-proliferation cooperation as ties between the two sides have hit their lowest point since the Cold War, but the Kremlin suggested it could review the move if Washington changed tack.

Putin charged earlier this year that the United States was not honouring the deal by disposing of plutonium in a way that allowed it to retain its defence capabilities.

The decree published Monday states that Russia is pulling out of the agreement “due to a drastic change in circumstances, the appearance of a threat to strategic stability due to unfriendly actions of the United States toward Russia”.

It claimed that Washington was “unable” to carry out the terms of the agreement and that Moscow “must take urgent measures to defend Russian security”.

“It’s a symbolic gesture that demonstrates that the sides no longer cooperate in this sphere,” said independent military expert Alexander Golts, adding that it was not the first agreement to be suspended in the non-proliferation sphere.

Putin’s spokesman Dmitry Peskov told journalists that Washington has not honoured the deal and “Russia no longer thinks it possible to carry out the conditions of the agreement alone” due to “general tension” between the two countries.

A bill submitted by Putin to parliament on Monday, which asked lawmakers to support the agreement’s suspension, indicated that some quid pro quo could still keep the deal alive.

The bill said that the agreement could be reinstated if Washington moves US forces out of countries that became NATO members after 2000, ends “all sanctions” and compensates Moscow for the financial losses resulting from them.

Lawmakers can vote on the bill as early as Wednesday, when the State Duma convenes for the first time since being elected last month in a vote that saw the ruling United Russia party sweep some three quarters of the seats.

The US-Russian Plutonium Management and Disposition Agreement obliges Moscow and Washington to dispose of no less than 34 tonnes of weapon-grade plutonium by irradiating it or transforming it into so-called MOX (mixed oxide) fuel.

The building of a MOX fuel reprocessing plant was opposed in the United States in the wake of the 2011 Fukushima nuclear disaster in Japan over safety fears and high cost of the project, which is already billions of dollars over budget.

US energy officials have pushed for using another method of disposal, calling for plutonium to be mixed with other substances and stored underground, but Moscow argues that any method to dilute plutonium is reversable.

Russia is locked in its worst standoff with the West since the Cold War over its 2014 annexation of Crimea and the conflict in Ukraine, and the US has accused Putin of “nuclear sabre-rattling”.

Tensions between the two sides have also recently ratcheted up over the conflict in Syria, where Russia is flying a bombing campaign in support of US-foe Bashar al-Assad.
Russian President Vladimir Putin suspends the 2000 treaty with the United States on cleaning up weapons-grade plutonium (Plutonium Management and Disposition Agreement) (in Russian).