MOSCOW (AFP) - Russia on Monday warned the West against using a search for weapons of mass destruction in Syria as an excuse for ousting President Bashar al-Assad along the lines of the notorious hunt for deadly arms in Saddam Hussein's Iraq.

Russian Foreign Minister Sergei Lavrov questioned why UN Secretary General Ban Ki-moon was calling for a fact-finding mission in Syria by citing unproven claims of the regime's use of chemical weapons in December.

"This demand by the Secretary General with reference to a forgotten episode reminds us a great deal of attempts in Syria to introduce a practice analogous to that which existed in Iraq, when they were looking for weapons of mass destruction there," Mr Lavrov told reporters.

Russia was strongly opposed to the US-led invasion of Iraq in 2003 that toppled Saddam Hussein and has bitterly resisted foreign intervention in its close Middle East ally Syria.

Mr Lavrov - speaking during a joint press appearance with African Union Commission chief Nkosazana Dlamini-Zuma - accused some governments and other players of using the threat of chemical warfare as a pretext for insisting on a foreign invasion of Syria.

"There are governments and outside players that believe that all means are appropriate to overthrow the Syrian regime," said Mr Lavrov, apparently referring to Western and anti-Assad Arab governments.

"But the subject of using weapons of mass destruction is too serious - it should not be joked around with."

The US-led invasion of Iraq in 2003 was sparked by a search for weapons of mass destruction purportedly held by Saddam Hussein's regime that were never found.