Russia supplies Syria with only defensive weapons under existing contracts and in line with international law, said Russian Foreign Minister Sergei Lavrov.

"We supply weapons to all those who contracted legally, which is a universal rule," Lavrov said in an interview published Tuesday.

Defensive weapons and air defense systems are not capable of provoking military crimes in Syria, he said.

Lavrov denied allegations that the Syrian government has asked for Kalashnikov automatic rifles, grenade launchers and ammunition from Russia, saying he has not seen that request.

"This is not a contract to which we are committed. Those are two very different things," he said, adding Moscow did not take sides in the Syrian conflict.

The Russian top diplomat meanwhile accused the Syrian opposition of delaying an international conference on Syria. Endi