MOSCOW -- The Russian Foreign Ministry is calling for an independent probe by United Nations experts into what Syrian rebels alleged was a chemical weapons attack by government forces on the outskirts of Damascus.

The statement released on Friday said that Minister Sergey Lavrov and U.S. Secretary of State John Kerry had discussed the situation by telephone on Thursday, and concluded that they had a "mutual interest" in calling for the U.N. investigation.

The statement said Russia had called for Syrian President Bashar Assad's embattled government to co-operate with an investigation, but questions remained about the willingness of the opposition, "which must secure safe access of the mission to the location of the incident."

Russia has been one of Assad's key allies in the international arena.