Russia will continue supplying weapons to Syrian President Bashar Assad's government despite the country's escalating civil war, the head of Russia's state arms trader said Wednesday.

Anatoly Isaikin, the director of Rosoboronexport, said that Russia sees no need to stop arms trade with Syria as it isn't prohibited by the United Nations. He dismissed Western criticism of Russian arms sales to Assad's regime, saying that his company has only delivered defensive weapons.

"In the absence of sanctions, we are continuing to fulfill our contract obligations," Isaikin said at a news conference. "But these aren't offensive weapons. We are mostly shipping air defense systems and repair equipment intended for various branches of the military."

Moscow has been the main protector of Assad's beleaguered regime, joining with China at the U.N. Security Council to block attempts to impose sanctions over his crackdown on a 23-month-old uprising in which more than 60,000 have died.

For more than four decades, Syria has been Moscow's top ally in the region and has received billions of dollars' worth of missiles, combat jets, tanks, artillery and other military gear. It's the last Kremlin ally in the Middle East and hosts the only naval base Russia has outside the former Soviet Union.

As the rebel offensive against Assad has intensified, the Kremlin has sought to distance itself from Assad, signaling that it is resigned to him eventually losing power. But Moscow has continued to oppose sanctions against Damascus and warned that the fall of Assad's regime could plunge Syria even deeper into violence and also encourage the rise of extremist groups across the region.

Alexei Pushkov, the Kremlin-connected head of foreign affairs committee in the lower house of the Russian parliament, said Wednesday that Assad's downfall would create a "second Afghanistan" and reaffirmed that Russia would continue to reject the calls for the Syrian ruler's resignation as a precondition for peace talks.

Russia has bristled at Western demands to stop providing Assad with arms, arguing that its weapons trade with Damascus doesn't contradict international law. In June, a Russian-operated ship carrying helicopter gunships and air defense missiles was forced to turn back to Russia after its British insurer canceled coverage for the vessel.

Russia said the vessel was carrying three refurbished helicopters belonging to Syria, and criticized Britain for forcing the ship to turn back, saying that it wouldn't abide by European sanctions against the Assad regime.

The helicopters were repaired and sent back to Syria by a different Russian firm, and Isaikin insisted that his company hasn't shipped any combat planes or helicopters to Syria.

He said more deliveries will be conducted under existing contracts, but refused to give specifics.

Isaikin said that his company has a contract with Syria for the delivery of Yak-130 combat jets but so far has not shipped any. He didn't explain why no deliveries have been made, but the reason could be the aircraft's long production cycle.

Russian media reported last year that the contract was for 36 Yak-130s worth $550 million. The Yak-130 is a combat training jet that can also carry modern weapons for ground attack missions.

Isaikin didn't mention any other weapons systems which his company has delivered to Syria or is planning to ship in the future.

The Russian media said they included Pantsyr-S1 and Buk-M2 air defense systems and Bastion anti-ship missile system. The latter is armed with supersonic Yakhont cruise missiles that have a range of up to 300 kilometers (162 nautical miles) and provides a strong deterrent against an attack from the sea.