Representatives of the Syrian government and some armed opposition groups are meeting in the Kazakh capital, Astana, on Monday for talks aimed at implementing a lasting ceasefire agreement.
Though there have been several international initiatives aimed at bringing the war, now in its seventh year, to an end, the latest round of Astana talks is aimed at establishing four so-called "de-escalation zones" in mainly opposition-held areas of the country, with Russia, Turkey and Iran acting as guarantors.
The meeting is expected to call for a cessation of hostilities between anti-government groups and forces fighting on behalf of President Bashar al-Assad, for a period of at least six months.
The plan, which has not yet been published, will call for all aircraft to be banned from flying over these areas, rendering them no-fly zones.
Sources have told Al Jazeera that the October 30-31 meeting will also discuss the release of hostages, prisoners, delivery of food and aid to besieged areas, the transfer of dead bodies and the search for missing persons.
What areas will be 'de-escalation zones'?
The zones will cover four areas of Syria:
Zone 1: Parts of Idlib province, as well as parts of northeastern Latakia province, western areas of Aleppo province and northern areas of Hama province.
There are more than one million civilians in this zone and its rebel factions are dominated by Hay'et Tahrir al-Sham (HTS), an alliance largely controlled by Jabhat Fateh al-Sham, a former al-Qaeda affiliate.
Zone 2: Eastern Ghouta, in the northern Damascus countryside.
About 690,000 civilians live there.
Jaish al-Islam, a major rebel faction in eastern Ghouta, is participating in the Astana talks.
Zone 3: The Rastan and Talbiseh enclave in northern Homs province.
There are approximately 180,000 civilians in this zone and its network of rebel groups includes HTS.
Zone 4: The rebel-controlled south along the border with Jordan that includes parts of Deraa and Quneitra provinces.
Up to 800,000 civilians live there.
According to Syrian opposition sources, checkpoints will be positioned within the "de-escalation zones" to facilitate the free movement of unarmed civilians and humanitarian access to the areas.