In this photo released by the Syrian official news agency SANA, Syrians gather in a street that was hit by shelling, in the predominantly Christian and Armenian neighborhood of Suleimaniyeh, Aleppo, Syria,... (Associated Press) 
 
 MUNICH (AP) — Russia has proposed a March 1 ceasefire in Syria, U.S. officials say, but Washington believes Moscow is giving itself and the Syrian government three weeks to try to crush moderate rebel groups. 
 
 The United States has countered with demands for the fighting to stop immediately, the officials said Wednesday. Peace talks are supposed to resume by Feb. 25. 
 
 The talk of new ceasefire plans comes as the U.S., Russia and more than a dozen other countries meet in Munich to try to halt five years of civil war in the Arab country. The conflict has killed more than a quarter-million people, created Europe's biggest refugee crisis since World War II and allowed the Islamic State to carve out its own territory across parts of Syria and neighboring Iraq. 
 
 Russia says it is supporting Syrian President Bashar Assad's government as part of a counterterrorism campaign. But the West says the majority of its strikes are targeting moderate groups that are opposed to Assad and the Islamic State. 
 
 The most recent Russian-backed offensive, near Aleppo, prompted opposition groups to walk out of peace talks last month in Geneva, while forcing tens of thousands of civilians to flee toward the Turkish border. 
 
 The U.S. officials weren't authorized to speak publicly about private diplomatic discussions in the run-up to the Munich conference and demanded anonymity. One said the U.S. can't accept Russia's offer because opposition forces could suffer irreversible losses in northern and southern Syria before the ceasefire ever takes hold. 
 
 The officials said the U.S. counterproposal is simple: A ceasefire that is effective immediately and is accompanied by full humanitarian access to Syria's besieged civilian centers. 
 
 Secretary of State John Kerry, who arrived in Germany Wednesday, had talks planned late in the evening with U.N. peace envoy Staffan de Mistura and Adel al-Jubeir, the foreign minister of Saudi Arabia, a key backer of Syria's rebel groups. 
 
 The Obama administration has been trying for months to clinch a ceasefire and pave the way for a transition government in Syria that would allow parties to the conflict to concentrate on defeating the threat posed by the Islamic State and the al-Qaida-linked Nusra Front. 
 
 But after having long demanded Assad's ouster, the shift in the U.S. focus to combating terrorism has resulted in a confusing mix of priorities and a layered strategy in Syria that few understand, and even fewer see working. Beyond Russia, the administration has often struggled to keep its own allies such as Turkey and Saudi Arabia in line. 
 
 "We will approach this meeting in Munich with great hopes that this will be a telling moment," Kerry said Tuesday in Washington. His peace push coincides with Defense Secretary Ash Carter's attendance at a gathering in Brussels to hash out military options with NATO partners. 
 
 Brett McGurk, the Obama administration's point-man for defeating the Islamic State, said Russia's Aleppo offensive was having the perverse effect of helping the extremists by drawing local fighters away from the battle against IS and to the war against Syria's government. 
 
 "What Russia's doing is directly enabling ISIL," McGurk told the House Foreign Affairs Committee in Washington. 
 
 But the panel's top Democrat echoed some of the frustration of his Republican colleagues with the larger U.S. strategy. 
 
 "It seems as if we're only halfheartedly going after ISIS, and halfheartedly helping the (rebel) Free Syria Army and others on the ground," said Rep. Eliot Engel, D-N.Y. He urged a "robust campaign, not a tentative one, not one that seems like we're dragging ourselves in ... to destroy ISIS and get rid of Assad." 
 
 Kerry emphasized Tuesday that U.S. officials "are not blind to what is happening." He said the Aleppo battle makes it "much more difficult to be able to come to the table and to be able to have a serious conversation." 
 
 But the U.S. has staked its hopes for an end to the five-year civil war in Syria on the peace talks and Assad's eventual departure, saying the American public has no appetite for a military solution. 
 
 To that end, Washington has tempered its calls dating back to August 2011 for Assad to immediately leave power. And to get Russia on board, it now won't even say that Assad should be barred from running for re-election if and when a new Syrian constitution is drafted. 
 
 The ambiguity has emboldened Assad's supporters, Russia and Iran, while upsetting American allies in the Middle East, who are frustrated by a process that appears to lock the Syrian leader in place well into 2017 — and perhaps beyond. ||||| The United States, Russia and other world powers agreed Thursday to implement a nationwide “cessation of hostilities” in Syria’s civil war to start in one week in an effort to stop the carnage and allow delivery of humanitarian aid to besieged civilians. 
 
 The cease-fire will not apply to groups designated as terrorists -- namely, Islamic State and the Al Qaeda offshoot known as the Al Nusra Front -- so that Russia and the U.S.-led coalition can continue airstrikes against those positions. 
 
 But how that will play out is unclear: The U.S. has often accused Russia of claiming it was fighting Islamic State when in fact it targeted other opponents of the Syrian government. 
 
 The Russians also would be allowed to continue airstrikes against other, unspecified targets that they claim are terrorist groups. 
 
 U.S. Secretary of State John F. Kerry made the announcement after a meeting in Munich, Germany, that lasted hours beyond schedule, a sign of the torturous negotiations and deep levels of disagreement among the parties involved in the Syria crisis. 
 
 “Obviously, it’s been difficult,” Kerry said. 
 
 Kerry said details of the “cessation of hostilities” had yet to be worked out. That could include ways to monitor and verify the cease-fire. He said aid deliveries to the most desperate parts of Syria would begin within days. 
 
 "This is a pause that is dependent on the process going forward," Kerry said. But it will have the effect of stopping offensive actions at least temporarily, he said. 
 
 "The objective is to achieve a durable long-term cease-fire at some time," he said. 
 
 Russia, which is backing the Syrian government, had proposed a cease-fire to begin March 1. After days of bombing runs that U.S. officials say have killed civilians and moderate U.S.-backed rebels, Moscow has given its ally a clear military advantage. 
 
 The suspicion was that Russia would prefer a cease-fire to begin three weeks from now in order to provide time to finish crushing the rebels and return the besieged city of Aleppo, Syria’s largest, to President Bashar Assad’s control. 
 
 The United States, Saudi Arabia, other Arab gulf states and much of the West want to get rid of Assad, saying his brutality and willingness to use chemical weapons against his people make him more suited for a war crimes tribunal than a presidential palace. 
 
 But Russia and Iran remain Assad’s firm backers, and their forces have shifted the balance of power in Syria back to Assad after nearly five years of civil war. 
 
 U.S. and European diplomats rejected the Russian proposal, saying the cease-fire had to be immediate. 
 
 “The future of Syria and Syrians is in our hands,” European Union foreign policy chief Federica Mogherini said in Munich. 
 
 Earlier, Kerry started Thursday’s meeting with his Russian counterpart, Sergei Lavrov, and then joined other members of the so-called International Syria Support Group, a collection of 20 nations working on the conflict, which has fueled the largest refugee crisis in Europe since World War II and killed more than 200,000 people. 
 
 After the meeting concluded, Lavrov joined Kerry to announce the results. He bristled when a reporter asked him whether aid agencies were lying in regularly claiming that Russian airstrikes have killed civilians. "Some do lie," Lavrov said. 
 
 The Obama administration also wants a settlement in Syria to allow for more focused fighting to eliminate Islamic State militants, who have seized on the chaos to take over large swaths of Syria and Iraq before expanding now to Libya. 
 
 Kerry tweeted that he “made clear [to Lavrov] the need for immediate progress on humanitarian access, ceasefire.” 
 
 “We're going to have a serious conversation about all aspects about what's happening in Syria,” he told reporters in Munich. “We will talk about all aspects of the conflict.” 
 
 At the margins in the Munich talks, Russian and U.S. officials were far from agreement and instead traded accusations. 
 
 Moscow rejected a U.S. military statement Wednesday saying Russian warplanes had destroyed two hospitals in Aleppo. Russia insists the damage was the result of U.S. airstrikes. U.S. military and State Department officials denied the Russian claim. 
 
 More than 50,000 Syrian refugees have fled Aleppo and the surrounding area toward the border with Turkey, where they are in effect trapped. 
 
 Already reeling from the influx of more than 2.5 million Syrian and Iraqi refugees, Turkey has refused to allow more to enter. President Recep Tayyip Erdogan said doing so would further the “ethnic cleansing” that Assad is causing. He instead called for the establishment of havens in Syria. 
 
 The top human rights official for the United Nations, Zeid Raad Hussein, said the deterioration of conditions in Aleppo, where about 300,000 people may be trapped and under attack, was “grotesque.” 
 
 “The warring parties in Syria are constantly sinking to new depths, without apparently caring in the slightest about the death and destruction they are wreaking across the country,” said Hussein, the U.N. high commissioner for human rights. 
 
 The North Atlantic Treaty Organization said Thursday that it plans to deploy warships and surveillance planes to the Aegean Sea to monitor the crossings of thousands of Syrian refugees, who are risking their lives on a daily basis to escape civil war. 
 
 The NATO force will work with the European Union’s border management agency, Frontex, to stem trafficking and illegal migration, said NATO Secretary-General Jens Stoltenberg. 
 
 “This is not about stopping or pushing back refugee boats,” he said at a NATO ministerial meeting in Brussels. “NATO will contribute critical information and surveillance to help counter human trafficking and criminal networks.” 
 
 Another goal of the Munich talks is to persuade the warring parties to return to negotiations in Geneva on Feb. 25. The first attempt at negotiations broke down this month when opposition groups walked out over the Aleppo offensive. 
 
 There has been persistent disagreement over even the basics of who should be allowed at the negotiating table; Syria considers many of the opposition groups to be “terrorists,” the same label Turkey gives to several of the Kurdish groups. 
 
 Times staff writer W.J. Hennigan in Washington contributed to this report. 
 
 For more news about global affairs, follow @TracyKWilkinson on Twitter. 
 
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– Russia has proposed a March 1 ceasefire in Syria, US officials say, but Washington believes Moscow is giving itself and the Syrian government three weeks to try to crush moderate rebel groups. The United States has countered with demands for the fighting to stop immediately, officials say. The talk of new ceasefire plans comes as the US, Russia and more than a dozen other countries meet in Munich to try to halt five years of civil war in the Arab country. The Guardian reports that according to a new study from the Syrian Center for Policy Research, the war has killed or injured 470,000 people—11.5% of the population—and has also lowered life expectancy from 70 to 55 and almost "completely obliterated" the country's infrastructure. The most recent Russian-backed offensive, near Aleppo, prompted opposition groups to walk out of peace talks last month in Geneva, while forcing tens of thousands of civilians to flee toward the Turkish border. Sources tell the AP that the US can't accept Russia's offer of a March 1 ceasefire because moderate opposition forces could suffer irreversible losses in northern and southern Syria before it ever takes hold. Defense Secretary Ash Carter, meanwhile, says NATO military authorities have been ordered to draw up plans for how the alliance could help shut down illegal migration and people smuggling across the Aegean Sea. Three NATO allies—Turkey, Germany, and Greece—requested alliance participation in an international effort to help end Europe's gravest migration crisis since World War II.