The international envoy to Syria, Lakhdar Brahimi, says the Syrian government and some rebel groups have agreed to a truce during a religious festival.
However the Syrian foreign ministry says the army is still studying the proposal for a ceasefire during the Muslim festival of Eid al-Adha.
Rebels were split over the ceasefire plan, with one jihadist group saying it would not observe it, the BBC reports.
The main armed rebel group, the Free Syrian Army (FSA), said any ceasefire observed by the government would be reciprocated but added it doubted the regime would implement the truce.
The envoy, Lakhdar Brahimi, said he hoped to use the lull in fighting over Eid al-Adha, which starts on Saturday, to discuss a longer and more effective ceasefire.
Eid al-Adha, the Festival of the Sacrifice, is celebrated by Muslims to commemorate the willingness of Abraham to sacrifice his son Ishmael as proof of obedience to God.