Fighting eased in Syria on Saturday after a deal signed by government backers Russia and Iran and militant supporter Turkey to create four “de-escalation zones” began to take effect.
The multi-phase plan, signed on Thursday in the Kazakh capital Astana, is one of the more ambitious efforts to bring an end to Syria's six-year conflict.
It provides for a ceasefire, rapid deliveries of humanitarian aid and the return of refugees after the creation of “de-escalation zones” across stretches of eight Syrian provinces.
Those zones would see a halt to hostilities, including air strikes, and proposes the deployment of “third-party” monitoring forces.
It began coming into effect at midnight, according to Russia, but cosponsors have until June 4 to finalise the zones' borders.
The four main battlegrounds covered are the northwestern province of Idlib, parts of central Syria, the south, and the opposition enclave of Eastern Ghouta near Damascus.
Some of those areas had already seen a drop in violence by Saturday.
The skies were quiet over Idlib province, AFP's correspondent there said Saturday afternoon, but residents were anxious that the evening would bring renewed bombardment.
'Hostilities have dropped'
Syrian government warplanes could be heard from Eastern Ghouta around midday on Saturday, according to an AFP correspondent in the militant-held town of Douma.
The Syrian Observatory for Human Rights said there were skirmishes and shelling in several militant-held areas in the central province of Hama and in Eastern Ghouta.
“Despite these violations, we can still say that hostilities have dropped,” said Observatory head Rami Abdel Rahman.
The Britain-based Observatory said it had recorded no civilian casualties yet on Saturday, but that several fighters were killed in regime bombardment of Daraa and Aleppo provinces in the first reported deaths since the deal came into effect.
Several ceasefire deals have been agreed since Syria's conflict broke out in March 2011 but they have failed to permanently stem the fighting.
The new deal was penned by Turkey, which backs the opposition, as well as Russia and Iran, both supporters of Syrian President Bashar al-Assad.
It was reached in Astana during another round of negotiations to shore up a faltering truce deal brokered in December.
The agreement would initially last six months but could be extended by the guarantors.
It does not specify that the safe zones take effect immediately, but gives the three guarantor countries two weeks to form working groups to delineate them and then until June 4 to come up with the definitive boundaries.
Access to the areas will be controlled via security zones complete with checkpoints and observation posts.
Opposition 'concerned' by deal
The deal also calls for a continued fight against the militant Islamic State group and al Qaeda affiliate Fateh al-Sham Front, which could pose challenges.
In Idlib province in particular, Fateh al-Sham is a major component of the militant forces that control the area.
The Syrian government and militant groups are not signatories, and both sides spoke vaguely about “violations” of the agreement on Saturday.
A senior military source in Damascus said the army had noted breaches but was waiting for the zones to be fully delineated.
And a member of the militant delegation to the talks told AFP on Saturday that the opposition was “recording violations of the deal committed by the regime and its militias”.
“We will send this list to the Russians via the Turks,” the source said, speaking on condition of anonymity.
Several members of the militant delegation to the talks left the room shouting in protest as the signing ceremony got under way in Astana, angered by Iran's role.
Syria's leading opposition High Negotiations Committee also expressed “concern” about the deal, saying it “lacks safeguards and compliance mechanisms”.
Germany's foreign ministry on Saturday said it was concerned about reports of violations but that the successful implementation of the deal could be the first step towards a real ceasefire in Syria.
Washington has given the deal a guarded welcome, and United Nations chief Antonio Guterres said he was “encouraged” by it.
The UN is hoping that success on the ground could pave the way to a new round of political talks in Geneva later this month.