Russia, Turkey and Iran are expected to continue the talks with the Syrian regime and rebel groups on Tuesday.
The first day of peace talks between the Syrian regime and the opposition groups in Kazakhstan's capital Astana ended on Monday without any apparent breakthrough. But a source close to the talks said that it has given grounds for cautious optimism about potential progress.
The talks, which were brokered by Turkey and Russia in a bid to end Syria's six-year-war, have marked the first time rebel groups directly negotiate with the Syrian regime since the conflict began in 2011.
The rebels, however, refused to take part in face-to-face negotiations with the regime because of its ongoing bombardment and attacks near Damascus.
TRT World's Hasan Abdullah reports from Astana.
In indirect meetings, the regime has pushed for a "comprehensive" political solution to the conflict, insisting that rebels lay down their arms in exchange for an amnesty deal.
But rebels have said that the talks were meant to bolster a frail ceasefire that took effect in December. They said they were not seeking a political solution to the conflict at the talks and vowed to continue fighting if the peace talks fail.
The talks are scheduled to continue on Tuesday.
Meanwhile, the Syrian regime has been making progress fighting Daesh which is not subject to the ceasefire.
TRT World 's Shamim Chowdhury has more from Gaziantep, near the Syrian border.
Regime forces have recaptured five villages in the Aleppo countryside over the last 24 hours. They are now very close to the strategic town of al-Bab, a major stronghold for the terror group Daesh.
Russia also said that its forces carried out air strikes on Daesh near the eastern Syrian city of Deir Ezzor.