The tense battle to reach a nuclear deal between Iran and West An International Atomic Energy Agency (IAEA) inspector cuts the connections between the twin cascades for 20 per cent uranium enrichment at the Natanz facility, some 322kms south of Tehran, Iran. Picture: IRNA, Kazem Ghane Source: AP AFTER more than a decade of stalemate and threats, the clock starts today on the six-month initial phase of a deal that negotiators for Iran, the United States and five other world powers say could lead to a permanent agreement to defuse tensions over Iran's nuclear program. Beginning today, Iran has agreed to take steps to curtail some aspects of its nuclear program in exchange for $7 billion in relief from economic sanctions that the US and its allies have imposed on the Islamic republic. The measures are intended to build confidence between the two sides that a permanent deal would be respected by both and won't be used by the Iranians simply to get closer to building a nuclear weapon, as the United States has accused them of doing. But reaching a permanent deal - and removing from the world's problems the threat of a military strike against Iran - is hardly a certainty. The obstacles are many, and they come from both Iran and the United States. Hardliners on both sides oppose the interim deal, even as the Obama administration and supporters argue that it marks the first time Iran has agreed to limitations on its nuclear program. Iran's deputy Foreign Minister Abbas Araghchi, right, shakes hands with Director General of the International Atomic Energy Agency, IAEA, Yukiya Amano in Austria in October 2013. Picture: Hans Punz Source: AP "It's a huge step forward," said Daryl Kimball, executive director of Arms Control Association, a policy institute in Washington that's closely monitored the nuclear talks. It's not everything we want it to be, and it's not everything the Iranians want it to be, but it's far better than an unconstrained Iranian nuclear program. Starting Monday, according to the interim deal, President Hassan Rouhani's government is expected to halt uranium enrichment above normal fuel grade, stop adding centrifuges at enrichment plants, and end nuclear-related activities at the unfinished Arak heavy water reactor. It's agreed to submit to daily inspections from international experts. In return, the United States and other powers are expected to ease some sanctions and free up several billion dollars in frozen Iranian oil revenues on a staggered timetable. The European Union has suspended a range of sanctions against Iran after a deal to curb its nuclear program. Iran and the so-called P5-plus-one - UN Security Council permanent members the United States, France, Russia, China and the United Kingdom, plus Germany - took months to set forth the principles in the interim agreement, which they announced as a deal on November 24. Then it took several more weeks to work out the logistics of how the deal would be executed. The next phase will be even more complicated. This delicate first stage, analysts said, gives the international community an unprecedented window into Iran's long-shrouded nuclear activities and offers Rouhani's relatively moderate administration a chance to prove that there are benefits to moving Iran away from its status as a pariah state. Iranian President Hassan Rouhani sits at the 27th International Islamic Unity Conference in Tehran, Iran earlier this month. Picture: Vahid Salemi Source: AP Analysts who follow the nuclear talks say that mistrust is so high between Iran and the West that the compromise was a symbiotic "mutual hostage arrangement," as one observer put it. Put simply, each side has the ability to speed up or slow down its progress on benchmarks based on its perception of how well the opposite side is fulfilling its end of the bargain. But longstanding mutual mistrust, analysts say, isn't even the biggest stumbling block to this or future phases of a nuclear deal. In the United States, members of Congress who oppose any such agreement with Iran are trying to push through legislation that would add new sanctions, effectively violating the Obama administration's pledge in the interim deal to refrain from imposing new nuclear-related sanctions for the next six months. Such a reneging could embolden Rouhani's hard-line detractors in Iran who've criticised the recently installed president's efforts to ease Iran back into the international fold. An International Atomic Energy Agency (IAEA) seal on a piece of equipment at one of Iran's uranium enrichment facilities at the Natanz plan near Tehran, Iran. Reports say that a majority of the Senate is in favour of a new sanctions bill introduced by Senators. Robert Menendez, D-N.J., Mark Kirk, R-Ill., and Chuck Schumer, D-N.Y., that includes language the administration argues would torpedo any chance of a long-term deal by imposing unrealistic terms. For example, as noted by the journalist Ali Gharib in a blog post for Washington Monthly, the bill contains a "poison pill" with a demand for a halt to all uranium enrichment, a condition the Iranians repeatedly have rejected. "On enrichment, the new sanctions bill seeks to influence, even dictate acceptable American terms for a final deal," Gharib wrote. The White House is pushing Democratic lawmakers to oppose the bill, arguing that the opposition to the Iran deal doesn't make sense because the absence of a deal leaves two options for nations concerned with Iran's nuclear ambitions: accept the potential for a nuclear-armed Iran, or prepare for military confrontation with Iran over its program. European Union negotiator Robert Cooper and EU Foreign Policy Chief Catherine Ashton during the second day of talks between Iran and world powers on Iran's nuclear program at the historical Ciragan Palace in Istanbul, Turkey, on 22 January, 2011. Picture: Salih Zeki Fazlioglu Source: AP Already, as the Gharib blog noted, Iranian Foreign Minister Javad Zarif has warned that new sanctions would mean "the entire deal is dead." And there's concern, analysts say, of tit-for-tat legislation from Iran that would boost enrichment up to even 60 per cent, even closer to weapons-grade levels. "The flies in the ointment don't have to do with irreconcilable differences, but with elements on both sides that are intent on torpedoing the process," said Paul Pillar, an adjunct senior fellow at Georgetown University's Center For Security Studies, who spent nearly three decades in intelligence work focused on the Middle East and Persian Gulf. Politics aside, Pillar added, "There's no reasonable case to be made for this type of legislation at this point." Alireza Nader, a senior policy analyst at the Washington-based RAND research institute and author of Iran After the Bomb, suggested that the West should capitalise on this rare opening from a notoriously closed off and hostile Shiite Muslim theocracy. Rouhani's ability to deliver on the nuclear deal, Nader said, will have a ripple effect on his whole set of overtures to the West. So far, he added, even Iran's highest power, the Supreme Leader Ayatollah Ali Khamenei, has admonished Rouhani's critics in public statements that describe the nuclear negotiations as in the regime's best interests. Women walk through an old neighbourhood of central Tehran on January 20, 2014, as Iran announced that it would halt production of 20 per cent enriched uranium following the arrival of inspectors from the UN nuclear watchdog. Picture: Behrouz Mehri Source: AFP Nader warned, however, that nascent support from the religious authorities isn't guaranteed for months to come, especially if the United States brings new sanctions in violation of the agreement. "He promised the Iranian people he'd improve their standard of living, decrease Iran's political isolation and ease repression," Nader said. A lot of that depends on what happens with the nuclear deal. If he's unable to succeed with negotiations, then chances of economic and political liberalisation go down. Even if the first phase survives the congressional threats, plenty of other potential spoilers remain in the drafting of a longer-term, more comprehensive plan. Kimball, of the Arms Control Association, said four of the biggest sticking points are: Limitations on enrichment. The agreement calls for enrichment at a level commensurate with practical needs, Kimball said, but there's sure to be debate over "what's limited and what are practical needs." The future of Arak. The heavy water reactor is a year or so away from completion. The United States and its allies want to see the project scrubbed; the Iranians reject that idea. Kimball said the most likely compromise is converting it into a light water reactor that isn't as conducive to the production of plutonium, which can be reprocessed into nuclear weapons fuel. Questions about military aspects of the nuclear program. The International Atomic Energy Agency, the UN nuclear watchdog, wants answers to long-avoided questions about what it calls "military dimensions" to Iran's program. Kimball said the concern is "they may have engaged in weapons research." The scope and pace of sanctions relief from the P5-plus-one. The United States and its allies no doubt will seek to keep a tight hold on the purse strings so as to have leverage in case Iran fails to uphold its agreement. "These are tough," Kimball said. That makes the first-phase deal look simple.