US Secretary of State John Kerry said Sunday comments by Syria’s top diplomat that removing President Bashar al-Assad would cross a "red line", were an attempt to disrupt the peace process.

US Secretary of State John Kerry said Sunday comments by Syria's top diplomat that removing President Bashar al-Assad would cross a "red line", were an attempt to disrupt the peace process.

Speaking after talks with European allies in Paris, Kerry said Foreign Minister Walid Muallem's remarks were "clearly trying to disrupt the process... (he was) clearly trying to send a message of deterrence to others."

"But the fact is (President Bashar al-Assad's) strongest sponsors Russia and Iran have both adopted... an approach which dictates that there must be a political transition and that we must have a presidential election at some time," Kerry said on the eve of a new round of peace talks.

For his part, French Foreign Minister Jean-Marc Ayrault also said Muallem's comments were a "provocation."