Updated 12:25 pm: Syria's first peace talks faltered before they began on Friday, with opponents of President Bashar al-Assad refusing to meet his delegation unless it first signs up to a protocol calling for a transitional government.
Plans were ditched at the last minute for the two sides to sit down to talk face to face for the first time. Instead, they would each meet separately with a UN mediator, Lakhdar Brahimi, at the United Nations headquarters in Geneva.
The closed-door discussions were due to begin on Friday, two days after a formal opening conference was held in a poisonous atmosphere, with both sides and their global backers making uncompromising public speeches.
Any direct meeting appears unlikely for now.
The opposition says it has come to discuss a transition that will remove Assad from power. The government says it is there only to talk about fighting terrorism, and no one can force Assad to go.
Opposition delegates decided they would not meet the government delegation unless it endorsed "Geneva I," a 2012 protocol that calls for a political transition.
"We have explicitly demanded a written commitment from the regime delegation to accept Geneva I. Otherwise there will be no direct negotiations," opposition delegate Haitham al-Maleh told Reuters.
A UN spokeswoman confirmed Brahimi would meet the delegates separately: "There are no Syrian-Syrian talks at the moment," said Alessandra Vellucci. "I cannot tell you anything about what will happen in the next few days."