A UN negotiator is meeting members of both Syria's government and the opposition on Friday, in an effort to end the three-year civil conflict.
But despite hopes of a joint meeting between the two sides, mediator Lakhdar Brahimi is holding talks with each in a different room at a different time.
Both sides blame the other for the separate meetings.
The Damascus delegation has complained about defiant remarks made by the opposition chief Ahmed Jarba.
On Thursday Mr Jarba called President Assad and his regime a "political corpse" which could not be part of Syria's future.
For its part, the opposition has said it will not meet government delegates face-to-face until they have signed a written commitment accepting the Geneva communique drafted 18 months ago, which calls for a transitional government.
http://www.bbc.co.uk/news/world-middle-east-25872808