London (AFP) - World powers on Friday agreed a plan to cease hostilities in war-wracked Syria, but there are reasons to doubt its success.
Here are the key questions around the deal:
- How important is this announcement?
After the collapse of another round of peace talks in Geneva last week, it represents a political step towards ending the violence and offers hope to civilians caught up in the bloody war by promising humanitarian assistance.
"We should take it seriously," Michael Williams, visiting fellow at London's Chatham House international affairs think tank told AFP.
"The significance lies in the fact that this is an agreement between the US and Russia. They've taken ownership of this now. The parties, the opponents will notice this."
Early indicators of success will be the easing of the siege of civilian communities and improved access for humanitarian aid workers, said Yezid Sayegh, senior Associate at Carnegie Middle East Center.
"If there are no such signs, then that suggests that the regime and Russia intend... to bargain hard and extract every concession and advantage they can," he added.
But crucially the "cessation of hostilities" will not apply to Islamic State group and Al-Qaeda's local branch, Al-Nusra.
This leaves them open to attacks by President Bashar al-Assad's forces and his backers Russia, as well as the US-led coalition against IS and Kurdish forces.
So does it have any chance of success?
There are plenty of reasons to be sceptical.
Peace talks collapsed earlier this month after troops loyal to Assad, backed by Russian bombers and Iranian fighters, launched a major offensive on the key rebel stronghold of Aleppo.
The Russian air strikes and ground offensive by regime forces and pro-Assad militias have forced at least 50,000 people to flee, left the opposition virtually encircled and killed an estimated 500 people.
With a week until the implementation of the deal, there are fears of a violent dash to secure ground before the guns fall silent.
"That's the big worry," said Williams. "If Russia does step up its military action there's a risk that a week from now there's nothing to implement."
The ceasefire could give Assad time to plot the sealing off of Syria's border with Turkey, according to Emile Hokayem, senior fellow at the International Institute for Strategic Studies.
Rebel forces and their Turkish and Arab backers may also welcome the chance to recover from recent setbacks, while the lull could also give Kurdish fighters the opportunity to entrench their gains, he added.
What about Russia's role?
Russia has claimed all along that its bombing targets IS and Al-Nusra terrorists, even though evidence suggests it has mostly been against anti-Assad opposition groups.
Some fear the ceasefire deal will provide diplomatic cover while Russia's offensive continues.
"Talking about al-Nusra works in Russia's favour since so many rebel groups have ties to it," said Julien Barnes-Dacey from the European Council on Foreign Relations.
"This effectively gives the green light for them to carry on military action while paying lip-service to the agreement."
Hokayem from the International Institute for Strategic Studies said that Russia may exploit the ambiguity over its definition of terrorist groups to push its military advantage.
"The question is: if Russia does so, what are the Americans and others ready to do? Is it still a matter of polite American wishes backed by no leverage and little credibility?"
Ominously, as the deal was being negotiated in Munich, Assad vowed in an interview with AFP to retake the entire country, warning it could take a "long time".
Hardly the talk of a man looking for a negotiated settlement to a civil war that has claimed 260,000 lives and displaced half the population since it began in 2011.
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