Members of the rebel delegation: Ahmed Beri (L), chief of staff of the Free Syrian Army, and Ahmed Othman (R), commander of Sultan Murad group, attend the fourth round of Syria peace talks in Astana on May 4, 2017.

:: Powerbrokers Russia, Iran and Turkey struggled Wednesday to hammer out details on a plan for safe zones in Syria at a fifth round of peace talks in the Kazakh capital Astana.

Moscow and Tehran, which back Syrian President Bashar al-Assad, and rebel supporter Ankara agreed in May to establish four “de-escalation” zones in a potential breakthrough towards calming a war that has claimed an estimated 320,000 lives since March 2011.

While fighting dropped off in the weeks after the deal, it has ratcheted up in some areas since, and the international players have yet to finalize the boundaries of the zones or determine who will police them.

In a bid to thrash out the details of the plan, participants were holding a string of closed-door meetings for a second day in Astana, with a joint session bringing together all players, including representatives of the Syria regime and rebels, expected later Wednesday.

Rebel representatives at the talks were tight-lipped about progress, with one delegation member telling AFP only that “bilateral discussions are ongoing”.

But a source close to the Syrian rebel delegation told AFP that Turkey, Russia and Iran had “prepared seven documents to help implement a ceasefire in Syria and deploy ground forces in predetermined zones.”

The documents would not be signed this round but would probably be adopted at a conference next week in Tehran, the source said.

The source added that Iran had been proposed as a potential monitor for the de-escalation zone in the central province of Homs but that rebels would refuse any role for Tehran’s forces there.

Turkish and Russian forces are likely to be deployed in the northern de-escalation zone’s “buffer territory, separating the opposition and regime” in parts of Idlib and neighbouring Aleppo provinces, the source said.

‘Essentially’ agreed

Moscow’s negotiator Alexander Lavrentiev insisted late Tuesday that the borders of two zones — in rebel-held parts of Homs and around Eastern Ghouta close to Damascus — were “essentially” agreed.

But there were “still questions” about the safe zone meant to cover the Idlib province on the Turkish border and “some reservations” about another one across swathes of southern Syria, he said.

If requested Russia could send military police to patrol buffer zones between the government and rebel armies, he said, and foreign peacekeeping forces could be deployed within weeks once a deal is signed.

Russia has argued the agreement will provide moderate rebels with security and help focus attacks against jihadist groups such as Fateh al-Sham and ISIS.

Syria’s conflict evolved from a bloody crackdown on protests in 2011 into to a devastating war that has drawn in world powers, including Russia and a US-led international coalition.

Russia has been pushing the talks in Astana since the start of the year as it seeks to pacify Syria after its game-changing intervention on the side of Assad.

The talks have largely seen the West sidelined, but they are intended to complement broader political negotiations the United Nations is backing in Geneva, which are due to restart next week.