Syria accused Western powers on Tuesday of trying to wreck prospects for a negotiated settlement to the country's 2-1/2-year conflict by imposing preconditions on the peace process and supporting rebel fighters.

The comments, highlighting the precariousness of any international mediation between Syria's two warring parties, followed a meeting of foreign ministers from the United States, France and Britain a day earlier. They warned there would be consequences if President Bashar al-Assad did not hand over Syria's chemical weapons.

A U.S.-Russian deal to remove the weapons averted the immediate prospect of a U.S. military strike against Syria, but U.S. Secretary of State John Kerry insisted it offered Assad "no lifeline" and that he had "lost all legitimacy".

Syrian state news agency SANA quoted an unnamed foreign ministry official as saying the comments by the Western powers "exposed the truth of their aims in Syria" and their desire to impose their will on the Syrian people.

"Discussion of political and constitutional legitimacy in Syria is the exclusive right of the Syrian people," it said.

The agreement to remove chemical agents by mid-2014 was seen as a diplomatic success for foreign powers that might reinvigorate efforts to set "Geneva 2" peace talks.

Geneva 2 seemed stalled indefinitely after a poison gas strike outside Damascus that killed hundreds of people. The opposition and Western powers blame Assad for the attack.

The opposition has refused to attend Geneva 2 talks if they do not require that a final deal include the removal of Assad, whose family has ruled Syria for four decades.

Kerry's comments appeared aimed at assuaging opposition complaints that the diplomatic efforts on chemical weapons was restoring Assad's legitimacy.

Western powers have given some support to insurgents fighting to overthrow Assad but have hesitated to give them sophisticated weaponry because of rebel divisions and the dominance of hardline Islamist factions.

SANA accused Western powers of trying to prolong the conflict and said their stated commitment to a negotiated solution "contradicts their continuing attempts to preempt the political process and impose preconditions on it and their continuing support for groups practicing violence and terrorism in Syria."

The SANA statement insisted Assad would remain in power "as long as the people desired it," contradicting one of the primary opposition demands that he be removed.

"Whoever is not pleased by this reality should not go to the Geneva conference," the SANA statement said.

More than 100,000 people have been killed in the conflict, which started as a peaceful protest movement in March 2011. – Reuters