Russian Foreign Minister Sergei Lavrov on Sunday warned against what he called unfounded claims that Syria has chemical weapons, as the United Nations Security Council investigates deadly chlorine gas attacks.

Russian Foreign Minister Sergei Lavrov on Sunday warned against what he called unfounded claims that Syria has chemical weapons, as the United Nations Security Council investigates deadly chlorine gas attacks.

His comments came after Russia on Friday backed the setting up of a UN Security Council panel to identify who is behind the chlorine attacks, which the West blames on the Damascus regime.

Lavrov said the operation to remove chemical weapons from Syria was successful, and that all claims to the contrary should be checked.

"This problem was successfully resolved," he said of Syria's chemical weapons stocks in a statement.

Syria in 2013 had agreed to turn over its chemical arsenal and disable production sites after the United States threatened military action over a sarin attack outside Damascus.

"Sometimes publications come out that there could be undeclared chemical weapons in Syria. This is all being checked, here we must avoid unfounded accusations," Lavrov said Sunday.

"We have every basis to consider that Syria will continue cooperating closely," he added.

Russia's top diplomat reiterated Russia's backing for President Bashar al-Assad, arguing that the US-led coalition should overcome its "persistent rejection" of cooperation with the Syrian government in the fight with the so-called 'Islamic State of Iraq and the Levant' (ISIL) takfiri group.

"We still think this objective is achievable," he said.

Lavrov on Tuesday is set to meet his Saudi counterpart Adel al-Jubeir in Moscow to discuss the situation in Syria and Yemen and ways to combat ISIL.

Lavrov stressed that international powers should unite against ISIL, calling it a "common enemy."

He referred to a map drawn up by ISIL showing its plan to control the sites of Mecca and Medina in Saudi Arabia which are sacred to Muslims.

"Members of this terrorist organization have promised to blow up Muslim sacred sites because they consider them to be a reflection of 'incorrect' Islam. This is a terrible organization," he said.