BEIRUT - A Syrian opposition official said a fragile cessation of hostilities that took force early on Saturday faced "complete nullification" because of government attacks he said violated the agreement drawn up by the United States and Russia.
Countries backing the Syria peace process will meet at 3 p.m. (1400 GMT) in Geneva on Monday as France demanded information about attacks in breach of the cessation of hostilities.
Asaad al-Zoubi, head of the Saudi-backed opposition High Negotiations Committee's delegation to peace talks, said the truce had collapsed before it started, Al Arabiya al Hadath TV reported. "We are not facing a violation of the truce... we are facing a complete nullification," he said, and "we have alternatives to protect our people" if the international community could not. "I believe the international community has totally failed in all its experiments, and must take real, practical measures towards the regime," Zoubi said, without elaborating.
He added there were "no indicators" that the ground was being prepared for peace talks, which the United Nations has said it plans to reconvene on March 7.
Talks in Geneva in early February collapsed before they got off the ground, with rebels saying they could not negotiate while they were being bombed.
Since the cessation of hostilities came into effect government and Russian warplanes have struck areas in several western provinces of Syria, according to monitors. A Syrian military source said on Saturday the army had committed no violations.
Syrian state media said armed groups had fired dozens of mortar rounds in Latakia province on Sunday. Rebels in the area denied the reports.
Syria's opposition said on Sunday it would stick to the cessation of hostilities despite a number of violations by Syrian government forces.
The plan does not apply to Islamic State and the al Qaeda affiliate Nusra Front, which Moscow and Damascus have said they will continue to target. The opposition fears they will use this as a pretext to target other rebel groups.
The United Nations hopes the cessation of hostilities agreement, which is less binding than a formal ceasefire and was not directly signed by the Syrian warring sides, can precede a more formal ceasefire.