Talks in Geneva between Syria's government and opposition continue, despite no sign of progress.
The opposition called Wednesday for creation of a transitional governing body that would oversee a ceasefire under U.N. monitoring. The plan was presented to Syrian government negotiators and to international mediator Lakhdar Brahimi.
An opposition spokesman, Louay Safi, said there was no immediate Syrian government response to the proposal.
Damascus has repeatedly said negotiations must focus first on fighting terrorism, and not creation of a transitional government.
Brahimi is preparing to meet with diplomats from the two nations that helped organize the peace talks.
The United Nations says a planned meeting Friday between Brahimi, Russian Deputy Foreign Minister Gennady Gatilov and U.S. Under Secretary of State Wendy Sherman has been moved up to Thursday.