Russia said on Monday it was concerned the chances of foreign military intervention in Syria were growing following reports of Israeli air strikes around Damascus which were a source of "particular alarm".

"We are seriously concerned by the signs of preparation of global public opinion for possible armed intervention in the long-running internal conflict in Syria," Russian Foreign Ministry spokesman Alexander Lukashevich said in a statement.

He suggested those concerns stemmed in part from media reports about the alleged use of chemical weapons in the conflict that has killed more than 70,000 people in two years.

Russia is a long-standing arms supplier to Damascus and has protected President Bashar al-Assad by using its veto power in the U.N. Security Council to block Western-backed efforts to push him from power or increase pressure on his government to end violence.

Russia was also analysing the "reports of Israeli air strikes on May 3 and May 5 on sites in the suburbs of Damascus, which caused particular alarm," Lukashevich said.

"The further escalation of armed confrontation sharply increases the risk of creating new areas of tension, in addition to Syria, in Lebanon, and the destabilisation of the so far relatively calm atmosphere on the Lebanese-Israeli border."

"The internationalisation of the extremely dangerous and destructive internal conflict in Syria must not be permitted," he said, calling for "decisive efforts aimed at shifting the events in Syria into a peaceful channel."

Assad's government has condemned the air strikes as tantamount to a "declaration of war" and threatened unspecified retaliation.

A senior Israeli lawmaker said on Monday the strikes were not aimed to weaken Assad in the face of more than a two-year-old rebellion against his rule, but rather ensure Lebanon's Hezbollah, an ally of Assad, do not receive hi-tech weaponry. – Reuters