"France and other European countries have submitted a proposed resolution to the UN Security Council, which has been blocked by Russia and China," Prime Minister Francois Fillon said on Europe 1 radio.

"This is no longer acceptable," he declared, branding Monday's attack on his government's Damascus embassy, in which three French personnel were wounded, "extremely violent" and warning that Assad's regime was losing its grip.

"At the United Nations we are currently working with the Security Council to see if they can take up this issue," Foreign Minister Alain Juppe said in a separate interview with France Info radio.

"Once again, we call on Syrian authorities to do their duty. All governments should ensure the security of embassies and diplomatic missions. We call on the Syrian authorities to do this immediately," he said.

The foreign ministry said Monday that three French staff were wounded in the attack, which forced guards to fire three warning shots, while Washington said no staff were injured in a similar clash at the US compound.

As Syrian security forces looked on, Assad supporters smashed their way into the French embassy compound with a battering ram, broke windows and destroyed the ambassador's car, according to a spokesman in Paris.

Pro-democracy protests erupted in Syria in mid-March, bringing opponents of Assad's rule into the streets, and triggering a brutal crackdown by security forces that has killed 1,300 civilians, according to activists.

Last week, the French and US ambassadors to Syria made high-profile visits to the restive city of Hama ahead of a major banned street protest in a gesture of support to the civilian victims of the violence.

The regime reacted with fury, accusing the Western powers of fomenting unrest, and on Monday government security forces allowed pro-government mobs to attack the diplomatic missions.