Amman, Nov 6 (IANS/RIA Novosti): The Syrian authorities have assured Moscow that there will be no use of chemical weapons against rebel forces, Russia's foreign minister said Tuesday.

"I rule out the use by the [Syrian] regime of chemical weapons," Foreign Minister Sergei Lavrov told journalists. "We have received the appropriate assurances."

Lavrov said Russia had also asked Syria to make a similar pledge to western powers.

Syria has not signed the international Chemical Weapons Convention and is believed to possess mustard gas and sarin, an extremely toxic nerve agent.

Western powers have warned Assad that any use of chemical weapons would be unacceptable.

US President Barack Obama has told Syria that the movement or use of chemical weapons would have "enormous consequences."

A major who defected from Assad's embattled regime told The Times newspaper last month that the authorities would only use chemical weapons as a "last resort."

"We discussed this as a last resort - such as if the regime lost control of an important area," Major General Adnan Sillu said after arriving in Turkey.

Speaking in the Jordanian capital of Amman, Lavrov, said Russia was winding down arms sales to Assad's regime.

"We will conclude the deliveries of weapons under old contracts," he said.

Russia has been criticised by Western powers over its ongoing arms deliveries to Syria, its sole remaining ally in the Arab world.

But Moscow says the weapons are purely defensive in nature and in line with international law.