HANGZHOU, China (AP) — President Barack Obama and Russian President Vladimir Putin on Monday failed to force a breakthrough in negotiations over a cease-fire for Syria, but agreed to keep looking for a path to provide humanitarian relief to thousands of besieged civilians in the civil war-ravaged country.

After a 90-minute huddle on the sidelines of an economic summit, the two leaders directed their top diplomats to return to talks quickly, likely later this week, according to a senior administration official who briefed reporters on the meeting. The official would not be named discussing the private discussion, which also covered U.S. concerns over cybersecurity and the situation in Ukraine.

The official said the U.S. was eager to find an agreement quickly, mindful of the deteriorating conditions around the besieged city of Aleppo. But U.S. was wary of enter a deal that would not be effective. The two leaders used the talk to clarify sticking points, the official said.

The conversation came hours after U.S. and Russian negotiators acknowledged that a recent round of intense talk had come up short. Secretary of State John Kerry and Russian foreign minister Sergey Lavrov have for weeks been trying to broker a deal that would curb the violence between the Syrian President Bashar Assad's government forces and moderate rebels backed by the U.S.

The strategy has hinged on the two sides agreeing to closer militarily coordination against extremist groups operating in Syria. But Obama has expressed skepticism that Russia would hold to its agreement. In recent days, the State Department has said it is seeking a nationwide cease-fire between Assad's military and the rebels, rather than another "cessation of hostilities" that is time-limited and only stops fighting in some cities and regions.

Associated Press writer Kathleen Hennessey contributed to this story. </s> The United States and Russia hailed a breakthrough deal on Saturday to put Syria’s peace process back on track, including a nationwide truce effective from sundown on Monday, improved humanitarian aid access and joint military targeting of banned Islamist groups.

 ‘Today, Sergei Lavrov and I, on behalf of our presidents and our countries, call on every Syrian stakeholder to support the plan that the United States and Russia have reached, to … bring this catastrophic conflict to the quickest possible end through a political process,’ US secretary of state John Kerry told a news conference after marathon talks in the Swiss city.

 Russian foreign minister Sergei Lavrov said that despite continuing mistrust, the two sides had developed five documents that would revive a failed truce agreed in February and enable military coordination between the US and Russia against militant groups in Syria.

 Both sides agreed not to release the documents publicly.

 ‘This all creates the necessary conditions for resumption of the political process, which has been stalling for a long time,’ Lavrov told a news conference.

 The deal followed talks that stretched late into Friday night and several failed attempts to hammer out a deal over the past two weeks. The announcement on Friday was delayed as Kerry and US negotiators consulted with officials in Washington.

 ‘The Obama administration, the United States, is going the extra mile here because we believe that Russia, and my colleague (Lavrov), have the ability to press the Assad regime to stop this conflict and to come to the table and make peace,’ he said.

 Previous efforts to forge agreements to stop the fighting and deliver humanitarian aid to besieged communities in Syria have crumbled within weeks, with the United States accusing Assad’s forces of attacking opposition groups and civilians.

 Kerry said the ‘bedrock’ of the new deal was an agreement that the Syrian government would not fly combat missions in an agreed area on the pretext of hunting fighters from the banned Nusra Front, an al-Qaeda affiliate in Syria.

 ‘That should put an end to the barrel bombs, and an end to the indiscriminate bombing, and it has the potential to change the nature of the conflict.’

 Under the agreement, Russian-backed government forces and opposition groups, supported by the United States and Gulf States, would halt fighting for a while as a confidence building measure. During this time, opposition fighters will have the chance to separate from militant groups in areas, such as Aleppo, where they have become intermingled.

 If the truce holds from Monday, Russia and the United States will begin seven days of preparatory work to set up a ‘joint implementation centre’, where they will share information to delineate territory controlled by Nusra and opposition groups.

 Both warring sides would pull back from the strategic Castello Road in Aleppo to create a demilitarised zone, while opposition and government groups would both have to provide safe and unhindered access via Ramouseh in the south of the city.

 ‘We must go after these terrorists,’ Kerry said. ‘Not indiscriminately, but in a strategic, precise and judicious manner so they cannot continue to use the regime’s indiscriminate bombing to rally people to their hateful crimes.’

 All sides in the conflict would need to adhere to the nationwide truce, Kerry added, cautioning opposition fighters that if they did not separate from Nusra they would not be spared from air attacks.

 ‘This requires halting all attacks, including aerial bombardments, and any attempts to gain additional territory at the expense of the parties to the cessation. It requires unimpeded and sustained humanitarian access to all of the besieged and hard-to-reach areas including Aleppo.’

 Pentagon and US intelligence officials have spoken out against the idea of closer military cooperation with Russia, in particular the sharing of locations of opposition groups that have fought to topple Assad.

 US defense secretary Ash Carter, who only days ago delivered a forceful speech in England criticizing Russia, has long been skeptical of Moscow’s intentions in Syria.

 The Pentagon said in a statement it would carefully monitor the ‘preliminary understanding’ agreed on Friday and cautioned the Assad regime and its backer, Russia, to stick to deal requirements.

 ‘Those commitments must be fully met before any potential military cooperation can occur,’ Pentagon spokesman Peter Cook said. ‘We will be watching closely the implementation of this understanding in the days ahead.’

 The United States and Russia have backed opposite sides in Syria’s civil war, with few signs of an end in sight to more than five years of conflict, which killed more than 400,000 people and drove tens of thousands of refugees into Europe.

 The United Nations said on Friday the Syrian government had effectively stopped aid convoys this month and the besieged city of Aleppo was close to running out of fuel, making the talks even more urgent.

 The UN special envoy for Syria, Staffan de Mistura, welcomed the announcement, saying in a statement that it had provided ‘clear rules’ for a cessation of hostilities and would allow warring sides to resume political talks on a transition. </s> HANGZHOU, China (Reuters) - U.S. President Barack Obama and Russian President Vladimir Putin had a longer-than-expected discussion on Monday about whether, and how, they could agree on a ceasefire deal in war-torn Syria, a senior U.S. administration official said.

Obama and Putin spent about 90 minutes in a "constructive" meeting about getting humanitarian aid into the country, reducing violence, and cooperating on combating militant groups, the official told reporters.

In talks earlier on Monday, U.S. Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov were unable to come to terms on a ceasefire for the second time in two weeks, with U.S. officials stressing they would walk away if a near-term pact could not be reached.

Obama and Putin did not get into the finer details of a deal, but made progress to clarify "the remaining gaps" and directed Kerry and Lavrov to meet as early as this week to keep working on a deal, the official told reporters.

"If an agreement can be reached, we want to do so urgently, because of the humanitarian situation. However, we must ensure that it is an effective agreement," the official said.

"If we cannot get the type of agreement we want, we will walk away from that effort."

A cessation of hostilities agreement brokered by Lavrov and Kerry in February unraveled within weeks, with Washington accusing Syrian President Bashar al-Assad's forces of violating the pact.

State Department officials have declined to elaborate on what the sticking points are preventing a deal, though the U.S. official said the remaining differences revolved around how the plan would be implemented.

Russia has insisted that it cannot agree to a deal unless opposition fighters, backed by the United States and Middle East allies, are separated from al-Qaeda linked militants they overlap with in some areas.

Obama and Putin also discussed the conflict in Ukraine - a crisis that Obama had earlier discussed with German Chancellor Angela Merkel and French President Francois Hollande.

The White House wants to determine whether the Minsk ceasefire can be implemented beforeObama leaves office in January, or whether economic sanctions on Russia will need to be extended, the official said. </s> HAMBURG, Germany (AP) — The United States and Russia have reached agreement on a cease-fire in southwest Syria, three U.S. officials said Friday as President Donald Trump held his first meeting with Russian President Vladimir Putin.

The deal marks a new level of involvement for the U.S. in trying to resolve Syria’s civil war. Although details about the agreement and how it will be implemented weren’t immediately available, the cease-fire is set to take effect Sunday at noon Damascus time, said the officials, who weren’t authorized to discuss the cease-fire publicly and spoke on condition of anonymity.

Jordan and Israel also are part of the agreement, one of the officials said. The two U.S. allies both share a border with the southern part of Syria and have been concerned about violence from Syria’s civil war spilling over the border.

The deal is separate from “de-escalation zones” that were to be created under a deal brokered by Russia, Turkey and Iran earlier this year. The U.S. was not a part of that deal. Follow-up talks this week in Astana, Kazakhstan, to finalize a cease-fire in those zones failed to reach agreement.

Previous cease-fires in Syria have collapsed or failed to reduce violence for long, and it was unclear whether this deal would be any better.

Earlier in the week, Syria’s military had said it was halting combat operations in the south of Syria for four days, in advance of a new round of Russia-sponsored talks in Astana. That move covered southern provinces of Daraa, Quneitra and Sweida. Syria’s government briefly extended that unilateral cease-fire, which is now set to expire Saturday — a day before the U.S. and Russian deal would take effect.

The new agreement to be announced Friday will be open-ended, one U.S. official said, describing it as part of broader U.S. discussions with Russia on trying to lower violence in the war-ravaged country. Officials said the U.S. and Russia were still working out the details as Trump and Putin concluded their more than two-hour meeting on Friday.

The U.S. and Russia have been backing opposing sides in Syria’s war, with Moscow supporting Syrian President Bashar Assad and Washington supporting rebels who have been fighting Assad. Both the U.S. and Russia oppose the Islamic State group in Syria.

The U.S. has been wary of letting Iran gain influence in Syria — a concern shared by Israel and Jordan, neither of which wants Iranian-aligned troops amassing near their territories. A U.S.-brokered deal could help the Trump administration retain more of a say over who fills the power vacuum left behind as the Islamic State is routed from additional territory in Syria.

Though U.S. and Russian officials had been discussing a potential deal for some time, it didn’t reach fruition until the run-up to Trump’s meeting with Putin on the sidelines of the Group of 20 economic summit in Germany, officials said.

Before Trump’s meeting with Putin — his first with the Russian leader — Secretary of State Rex Tillerson signaled that Syria’s civil war would be high on the agenda. Tillerson said in a statement before departing for Germany for the meeting that the U.S. remained open to cooperating with Russia through “joint mechanisms” to lower violence in Syria, potentially including no-fly zones.

“If our two countries work together to establish stability on the ground, it will lay a foundation for progress on the settlement of Syria’s political future,” Tillerson said on Wednesday.

Moscow reacted angrily when the U.S. downed a Syrian jet last week after it dropped bombs near the U.S.-backed Syrian Democratic Forces conducting operations against the Islamic State group. Russia warned its military would track aircraft from the U.S.-led coalition as potential targets over Syria and suspended a hotline intended to avoid midair incidents. </s> HAMBURG, Germany (AP) — The United States and Russia have reached agreement on a cease-fire in southwest Syria, three U.S. officials said Friday as President Donald Trump held his first meeting with Russian President Vladimir Putin.

The deal marks a new level of involvement for the U.S. in trying to resolve Syria’s civil war. Although details about the agreement and how it will be implemented weren’t immediately available, the cease-fire is set to take effect Sunday at noon Damascus time, said the officials, who weren’t authorized to discuss the cease-fire publicly and spoke on condition of anonymity.

Jordan and Israel also are part of the agreement, one of the officials said. The two U.S. allies both share a border with the southern part of Syria and have been concerned about violence from Syria’s civil war spilling over the border.

The deal is separate from “de-escalation zones” that were to be created under a deal brokered by Russia, Turkey and Iran earlier this year. The U.S. was not a part of that deal. Follow-up talks this week in Astana, Kazakhstan, to finalize a cease-fire in those zones failed to reach agreement.

Previous cease-fires in Syria have collapsed or failed to reduce violence for long, and it was unclear whether this deal would be any better.

Earlier in the week, Syria’s military had said it was halting combat operations in the south of Syria for four days, in advance of a new round of Russia-sponsored talks in Astana. That move covered southern provinces of Daraa, Quneitra and Sweida. Syria’s government briefly extended that unilateral cease-fire, which is now set to expire Saturday — a day before the U.S. and Russian deal would take effect.

The new agreement to be announced Friday will be open-ended, one U.S. official said, describing it as part of broader U.S. discussions with Russia on trying to lower violence in the war-ravaged country. Officials said the U.S. and Russia were still working out the details as Trump and Putin concluded their more than two-hour meeting on Friday.

The U.S. and Russia have been backing opposing sides in Syria’s war, with Moscow supporting Syrian President Bashar Assad and Washington supporting rebels who have been fighting Assad. Both the U.S. and Russia oppose the Islamic State group in Syria.

The U.S. has been wary of letting Iran gain influence in Syria — a concern shared by Israel and Jordan, neither of which wants Iranian-aligned troops amassing near their territories. A U.S.-brokered deal could help the Trump administration retain more of a say over who fills the power vacuum left behind as the Islamic State is routed from additional territory in Syria.

Though U.S. and Russian officials had been discussing a potential deal for some time, it didn’t reach fruition until the run-up to Trump’s meeting with Putin on the sidelines of the Group of 20 economic summit in Germany, officials said.

Before Trump’s meeting with Putin — his first with the Russian leader — Secretary of State Rex Tillerson signaled that Syria’s civil war would be high on the agenda. Tillerson said in a statement before departing for Germany for the meeting that the U.S. remained open to cooperating with Russia through “joint mechanisms” to lower violence in Syria, potentially including no-fly zones.

“If our two countries work together to establish stability on the ground, it will lay a foundation for progress on the settlement of Syria’s political future,” Tillerson said on Wednesday.

Moscow reacted angrily when the U.S. downed a Syrian jet last week after it dropped bombs near the U.S.-backed Syrian Democratic Forces conducting operations against the Islamic State group. Russia warned its military would track aircraft from the U.S.-led coalition as potential targets over Syria and suspended a hotline intended to avoid midair incidents.

On Twitter, reach Vivian Salama at https://twitter.com/vmsalama , Josh Lederman at https://twitter.com/joshledermanAP and Ken Thomas at https://twitter.com/KThomasDC </s> The new U.S.-Russia deal on the Syrian ceasefire could be a game changer in international efforts to end the bloody war in Syria. Or the deal, the product of marathon talks since mid-June between U.S. Secretary of State John Kerry and Russian Foreign Minister Sergei Lavrov, could easily unravel as so many previous agreements have.

It faces daunting challenges: a gaping lack of trust between Moscow and Washington, unruly and suspicious local proxies, unhappy outside players in Iran and in the Gulf states, a hodgepodge of legal loopholes and lack of viable enforcement mechanisms. Its successful implementation is hard to fathom, but there is no other plan.

For the outgoing Obama administration, it is their final attempt at halting the violence in Syria and creating a breathing space for a negotiated political transition before the new administration takes over in January 2017.

The goal is to end the attacks on civilians and freeze the war between the regime forces and moderate opposition groups while carrying on with the central U.S. mission in Syria — defeating the Islamic State — a terror group banned in Russia — and Al-Qaeda. The removal of Syrian President Bashar Assad from power, while still a necessary condition for the political transition, is no longer an immediate U.S. objective. For Kerry, it is a diplomatic mission to secure his legacy.

For Moscow, the deal offered by the United States is extremely advantageous and meets most of Russia’s political objectives for its one-year-old military intervention in Syria. It is perhaps the last available off-ramp leading to a dignified political exit from the war Russia could not win. The deal satisfies Moscow’s obsession with achieving the international status of an indispensable global player on a par with the United States.



It legitimizes its military intervention to save the Assad’s regime as a joint counterterrorism operation with the United States and recognizes Russia’s future role in Syria as a key partner for the incoming U.S. administration. It helps freeze the military situation on the ground that is advantageous to the Syrian regime and its allies, while creating conditions to further weaken the opposition. There is so much for Moscow to love in this deal that it is surprising it took three months to negotiate.



The key part of the new agreement is the dual-key arrangement for the U.S.-Russia targeting selection process which would give Washington veto power over Russian air operations in designated areas where the opposition is intermingled with Nusra fighters, while essentially grounding regime planes over much of Syria. The United States will have a considerable amount of say in where, when and how Russia could strike Syria, vetoing the use of dumb bombs, cluster munitions and air-fuel charges. This is the only way to end the indiscriminate bombing of the civilian areas that fueled the recruitment for the extremists.

Moscow, in its turn, would also have a veto over potential U.S. strikes on regime and allied targets, like cratering regime’s airfields with stand-off weapons (although Moscow allows Israel to bomb Syria at will). This dual-key arrangement will not affect freedom of air operations over Islamic State-held territory.

The renewed Cessation of Hostilities (CoH) — agreed in February, but since largely ignored by all sides — could create sufficient calm for the UN-sponsored political process to restart. The key requirement would be lifting of all sieges and allowing humanitarian aid deliveries to the besieged towns. Ending the siege of eastern Aleppo by the regime forces appears to be a key part of the agreement, with considerable attention paid to the security and logistical arrangements to deliver aid in a safe and secure way without clearing the city of its inhabitants and opposition fighters.

The key problem that could undo this U.S.-Russian agreement is the requirement for the vetted opposition groups to distance themselves on the ground from Nusra units which would then be jointly targeted by Russian and U.S. airstrikes. Nusra is locally embedded in northwestern Syria, particularly in the Idlib province, and is on its way to becoming a Sunni version of Hezbollah. For many rebel groups, distancing themselves from Nusra, much less fighting it, is no longer feasible, as this will weaken their front against the regime. Since the agreement does not ban regime or Russian artillery and missiles strikes against the Nusra-infiltrated targets or require their vetting by the United States, it allows Assad to torpedo the CoH seemingly at will if Russia stands by.



The success of the deal will largely depend on Moscow’s eagerness to end the fighting and extricate itself from the war on honorable terms by pressuring Assad into freezing the military situation (the last attempt in February-March 2016 failed miserably) and engaging in meaningful political dialogue with the opposition to secure a transfer of power to an inclusive Syrian government.

The odds are heavily stacked against the deal, but there is no better way forward. </s> HANGZHOU, China -- President Barack Obama and Russian President Vladimir Putin on Monday failed to force a breakthrough in negotiations about a cease-fire for Syria, but agreed to keep looking for a path to provide humanitarian relief to thousands of besieged civilians in the civil war-ravaged country.

After a 90-minute huddle on the sidelines of an economic summit, the two leaders directed their top diplomats to return to talks quickly, likely later this week, according to a senior administration official who briefed reporters on the meeting.

The official would not be named discussing the private discussion, which also covered U.S. concerns about cybersecurity and the situation in Ukraine.

The official said the U.S. was eager to find an agreement quickly, mindful of the deteriorating conditions around the besieged city of Aleppo. But the U.S. was wary of enter a deal that would not be effective. The two leaders used the talk to clarify sticking points, the official said.

The conversation came hours after U.S. and Russian negotiators acknowledged that a recent round of intense talk had come up short. Secretary of State John Kerry and Russian foreign minister Sergey Lavrov have for weeks been trying to broker a deal that would curb the violence between the Russian-ally Syrian President Bashar Assad's government forces and moderate rebels backed by the U.S.

The deal depends on the two sides agreeing to closer militarily coordination against extremist groups operating in Syria, something the Russians have long sought and the U.S. resisted.

Obama has expressed skepticism that Russia would hold to its agreement. The State Department has said it wants a nationwide cease-fire between Assad's military and the rebels, rather than another limited "cessation of hostilities" that has repeated failed in the past.

Obama's meeting with Putin comes as the Russia leader is playing a prominent role in the presidential campaign at home. U.S. officials blame Russian intelligence for a hack on the Democratic National Committee that resulted in a leak of emails damaging to its presidential nominee, Hillary Clinton. Putin has denied his government was involved, but cheered the release of the information.

The official said Obama raised concerns about cybersecurity issues with Putin, but would not detail the discussions.

Obama and Putin also discussed the conflict in Ukraine, where Russian-backed separatists have been fighting the government, and the implementation of the agreement to stop the violence, the official said. Obama met earlier with French President Francois Hollande and German Chancellor Angela Merkel on the same issue.

Josh Lederman of the Associated Press contributed to this story. </s> Hangzhou, China (CNN) US President Obama says an agreement with Russia on ending the violence in Syria is being hampered by "gaps of trust" between the two governments.

Asked by CNN's Michelle Kosinski about his meeting with Russian President Vladimir Putin, the President described it as "candid" and "blunt" focusing mainly on Syria and Ukraine.

Mr. Obama called the discussion on Syria "productive" about what a real cessation of hostilities would actually look like.

"We have had some productive conversations about what a real cessation of hostilities would look like that would allow us both... to focus our attention on common enemies."

No Syria deal between US and Russia

No Syria deal between US and Russia 01:48

No Syria deal between US and Russia

Obama added that currently the gaps have not been closed in negotiations between Russia and the US in a way that they think would "actually work." Obama urged Kerry and Lavrov to work together in the coming days to get aid to those in need.

Obama and his Russian counterpart Putin met Monday as talks between their governments on ending violence in Syria ended without an agreement.

Meanwhile, Putin told reporters that a deal with the US to "ease tensions in Syria" may come "within a few days," according to Russia's state news agency TASS.

"Against all odds we have a certain rapprochement and understanding of what we might do to ease tensions in Syria and achieve mutually acceptable solutions," TASS quoted Putin as saying.

As for further details on the agreement, Putin said, "It is early now to speak of any parameters of our agreements, but I hope very much that the agreements will be reached, and I have the grounds to believe that this may happen within a few days," according to TASS.

The two leaders conversed on the sidelines of the Group of 20 summit here for ninety minutes, a senior US official said, and worked to clarify gaps in negotiations over on the Syrian crisis. The pair also discussed Ukraine and Russia's cyber intrusions, the official said.

The exchange came after talks between Secretary of State John Kerry and his Russian counterpart Sergey Lavrov failed to result in a Syria ceasefire agreement. They had been working to negotiate a plan that would have boosted military cooperation between the two nations in an effort to better target terrorists and prevent civilian deaths.

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Negotiators failed to work through differences, and the talks have ended for now. Following Obama's meeting with Putin, an official said the leaders indicated a desire for Kerry and Lavrov to reconvene deliberations in the coming days.

"It was constructive," a US official said after the meeting, noting that all differences were not resolved. The official spoke anonymously to discuss a private conversation.

"It's clear now what our respective positions are," the official said. "And we'll see in coming days whether on Syria we can reach a near-term agreement. If we cannot get the type of agreement we want, we will walk away from that effort."

Differences between the two sides are technical, the official indicated, suggesting the divide was at a level that Obama and Putin wouldn't negotiate themselves.

"President Obama and President Putin were not going to get down into the weeds of the language of an agreement and the implementation associated with the agreement," the official said.

Photos of the session distributed by the Kremlin show the two leaders and aides, including Kerry and US National Security Adviser Susan Rice, seated around a table. The presidents appeared in congenial moods, with one photo showing Putin smiling broadly.

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Both Russian and US officials said the meeting -- which was held in a conference room at the G20 summit site here -- lasted longer than planned, and that leaders spent the bulk of their meeting discussing Syria.

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Cautious optimism

On Sunday, cautious optimism prevailed that a deal could be struck between Washington and Moscow, long at odds over policy in Syria. Kerry and Lavrov had been working "around the clock" to come to an agreement, Obama told reporters.

Russian forces have aligned with Syrian President Bashar al-Assad to target US-backed opposition fighters that Moscow and Damascus claim are terrorists. The campaign has spurred a humanitarian crisis and caused millions of Syrians to flee for Europe.

The US hopes to align with Russia to identify terrorist targets, including ISIS and the Nusra Front, a group formerly tied to al-Qaeda. Officials hope a ceasefire will help advance talks on a political transition that would lead to the resignation of Syrian leader Bashar al-Assad.

Any deal to end widespread suffering in Syria was likely to be met with doubt after past settlements, including a ceasefire agreed to in February, failed -- a fact Obama acknowledged on Sunday.

"Given the failure of previous cessations of hostilities to hold, we approach it with some skepticism," Obama said.

But he insisted any work toward easing the deeply troubling humanitarian crisis was valuable.

"It is worth trying," he said. "To the extent that there are children and women and innocent civilians who can get food and medical supplies and, you know, get some relief from the constant terror of bombings, that's worth the effort."

Russia and the US

A deal on Syria could place US-Russia ties in a firmer position as Obama prepares to leave office. Deep divides over Syria have marred Obama's relationship with Putin, adding to a litany of discord between the US and Russia that's driven relations to their lowest level since the Cold War.

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This week's interaction between the two men could be a final attempt to salvage what's become one of the most acrimonious relationships on the global stage. Putin's persistent support for the Syrian regime, Moscow's moves in Ukraine and the charge that Russia may be meddling in the US presidential contest have built a deeply antagonistic dynamic between the two leaders.

Obama said on Sunday that Russian participation was essential.

"Our conversations with the Russians are key because, if it were not for the Russians, then Assad and the regime would not be able to sustain its offensive," he said. </s> The Obama administration is hailing its new initiative with Russia to halt the warfare in Syria as a potential “turning point” in one of the bloodiest conflicts in recent history.

But the room for doubt that the complex agreement announced early Saturday will work is enormous, hardened by years of broken promises and cynical gambits by the warring parties and their backers.

On paper at least, both the U.S. and Russia come away from marathon negotiations with components they demanded.

If the agreement takes hold, Washington and Moscow would form a new military alliance laser-focused on Islamic State and Al Qaeda-linked terrorist groups, a cooperation seemingly unthinkable amid the two countries’ tense relations of late.

And it would finally spare the people of Syria — especially in the besieged city of Aleppo, where civilians are being killed daily — from steady bomb attacks and provide them with desperately needed sustenance under a temporary cease-fire and the opening of some humanitarian aid routes.

But once again, the world’s top diplomats have punted on the fate of Syria’s widely reviled, Russian-backed leader, President Bashar Assad, setting no clear provisions for his removal. That, in turn, leaves questions unanswered as to a permanent solution for the war in Syria, arguably one of the most vexing and tragically handled crises in the outgoing Obama administration.

Secretary of State John F. Kerry acknowledged both the make-or-break nature of the violence in Syria and efforts to decrease it, and the inherent difficulties of success.

“No one is building this based on trust,” Kerry said at a brief news conference in Geneva in the wee hours Saturday, with his partner in negotiations, Russian Foreign Minister Sergei Lavrov, at his side.

“But let me be clear: Out of all of this complexity there is emerging now a simple choice between war and peace; between human agony and humanitarian relief; between the continued disintegration of an ancient society and the rebirth of a united and modern nation.”

Kerry pointed to two key provisions in the agreement that he says can make a difference over past, failed cease-fires. First, the Assad government will be required to suspend aerial attacks by its helicopters and warplanes on civilian areas. Russia must use its influence to guarantee that, and Lavrov said the Syrian government was on board.

Second, the U.S. agreed to pressure “moderate” rebel groups opposed to the Syrian government to fully distance themselves from the Front for the Conquest of Syria, formerly known as Al Nusra Front, which the U.S. considers Al Qaeda’s branch in Syria. But that will be extremely difficult.

The front’s militiamen work so closely with several of the U.S.-supported rebel groups that they are, as Kerry put it, “marbleized.” They are among some of the toughest fighters in Syria and are widely regarded as the force that was able to partially break the government’s siege on Aleppo.

Under the plan, “a cessation of hostilities” is set to take effect at nightfall Monday, which is also the start of the Muslim Eid al-Adha holiday. If the cease-fire is “genuine” and verifiable, Kerry said, U.S.-Russian military cooperation will begin. That would include the sharing of intelligence ahead of bombing runs and joint selection of targets.

Critically, neither Kerry nor Lavrov announced the sort of robust, verification protocols that most experts said would be essential. Nor did the diplomats announce any punishment for violating the cease-fire, part of what caused an earlier such agreement in February to break down within weeks.

“With no kind of monitoring mechanism, it will be hard to get Russia and the U.S. to agree on who violated. That was the problem in February, in March, in April,” said Robert S. Ford, the last U.S. ambassador to Syria and now a fellow at the Middle East Institute in Washington. “Until the combatants and their leaders decide there is more for them in peace than in fighting, this is not sustainable.”

U.S. officials, skeptical of both Russia and Syria’s intentions, had wanted a longer period of calm than just one week but evidently relented. Kerry also agreed to move the Front for the Conquest of Syria higher on the list of targets, insisting that was not a concession because it is a dangerous extremist group.

Assad has repeatedly used talks and truces to play for time, according to aid workers, diplomats and military analysts.

His ostensible acceptance of the cease-fire in February, coupled with Russia’s entry into the war a year ago, helped government forces gain the upper hand in the five-year war that has killed at least half a million people and turned millions more into homeless refugees.

They bombed hospitals and used chemical weapons with impunity, medical personnel and human rights activists say.

If Syria’s intentions cannot be trusted, neither can the Russians, some Obama administration officials contend. Kerry encountered stiff resistance to new cooperation with Russia from Defense Department and intelligence officials.

Just three days ago, Defense Secretary Ashton Carter delivered a speech in London that was highly critical of Russia’s “coercion and aggression.” He said Russia’s territorial belligerence and its “unprofessional behavior in the air, in space and in cyberspace” made it an unreliable partner.

After the agreement was announced in Geneva, the Pentagon remained cautious. Commitments by the Russian and Syrian governments to abide by a sustained cease-fire “must be fully met before any potential military cooperation can occur,” department spokesman Peter Cook said. “We will be watching closely the implementation of this understanding in the days ahead."

Privately, senior U.S. defense officials said they were doubtful about the utility of any deal with the Russian military.

"Of course, I'm pessimistic. I mean, they're Russians. How could we trust them?" said one U.S. official, who wasn't authorized to speak publicly.

Since the beginning of Russian military involvement in the Syrian conflict a year ago, the Kremlin has angled to collaborate with the United States so they can share intelligence and targeting information.
The U.S. Obama administration and the Russian Putin administration agree to a Syrian peace deal. The deal is intended to end combat in specified areas and create a joint center of combat to fight ISIL and Al-Nusra Front.