President Barack Obama called his French counterpart Francois Hollande on Saturday before announcing his decision to ask Congress to back military action against Syria, a senior White House official said.

After British lawmakers voted on Thursday to reject their government's plan to join the U.S.-led action, France is the only Western power likely to take part in future strikes.

The French right distanced itself from President Francois Hollande over military action in Syria on Saturday and warned him not to be hasty in siding with any U.S.-led response.

Former prime minister Francois Fillon and the president of the main right-wing party, the UMP, Jean-Francois Cope have both warned of the dangers of military action against Damascus in response to an alleged chemical weapons attack which the U.S. says left 1,429 people dead.

Even as the world waited Saturday to hear when President Barack Obama was to order military strikes against Syria's chemical-armed regime,the U.S. leader was already under fire at home.

While the latest opinion polls show that the American public does not even support Obama's plan for a "limited, narrow" operation, his hawkish opponents demanded tougher action.

Rockets launched in a western-led attack against Syrian regime targets may pass through Lebanese airspace, reported As Safir newspaper on Saturday.

French military sources told the daily that the attack will place Lebanon at the forefront of the war against Syria, seeing as American warships have started to head to the Mediterranean.

France on Friday reaffirmed its will for "strong" action against the Syrian regime, a day after the British parliament's shock rejection of military strikes -- putting it in a position to become the United States' main ally in the Syria crisis.

The situation is a far cry from a decade back when Franco-U.S. ties hit a low over differences on Iraq and then-president Jacques Chirac's opposition to the Anglo-U.S. offensive against Saddam Hussein's regime.

Chinese Foreign Minister Wang Yi discussed the Syrian crisis with his French counterpart Laurent Fabius Friday and stressed the need to support U.N. inspectors investigating the alleged use of chemical weapons, state media reported.

Wang said it had yet to be established whether chemical weapons had been used and by whom, the official Xinhua news agency said.

U.N. leader Ban Ki-moon on Friday met with U.N. ambassadors from Britain, China, France, Russia and the United States after cutting short a visit to Europe over the Syria chemical weapons crisis.

Ban has been pressing U.S. President Barack Obama and other world leaders not to allow a military strike on Syria until U.N. experts have finished their work in the country.

Any military response to alleged chemical weapons use by the Syrian regime of Bashar Assad will likely rest squarely on U.S. shoulders after Britain's refusal to commit its forces.

Once again at the spearhead of a possible lightning strike against Syrian military targets, the United States has reinforced its naval units in the eastern Mediterranean and could get help from France.

French President Francois Hollande said a military strike on Syria could come by Wednesday and that Britain's surprise rejection of armed intervention would not affect his government's stand.

"France wants firm and proportionate action against the Damascus regime," he said in an interview to Le Monde daily on Friday. The French parliament is due to meet on Wednesday for an emergency Syria session.

France on Thursday sought an emergency U.N. Security Council meeting after a surge of fighting in eastern Democratic Republic of Congo, envoys said.

The meeting was called for Thursday after a U.N. peacekeeper was killed in a clash with M23 rebels near the key eastern city of Goma.