UN Arab League envoy Lakhdar Brahimi on Sunday meet Syrian President Bashar al-Assad, state-run television said.
Brahimi is trying to get the government and the rebels to implement a ceasefire during the four-day Muslim holiday of Eid al-Adha, which starts on October 26, dpa reported.
Opposition leaders who met Brahimi in Damascus welcomed the ceasefire proposal.
"The situation Syria has reached a dangerous level of violence which poses a threat to the independence and sovereignty of the country," Hassan Abdul-Azim, the head of the opposition National Coordination Body, was quoted as saying by Arab media.
The government said this week it was ready to discuss the proposal. Previous ceasefire agreements failed.
Brahimi has said there is a very slim chance that his peace efforts will succeed. Fighting between rebels seeking to overthrow al-Assad and government forces kills dozens of people every day.
The Britain-based Syrian Observatory for Human rights said a car bomb exploded in the Seryan neighborhood in the northern city of Aleppo. Casualties were reported.
It also reported heavy clashes in the Ghotta area east of Damascus.