The French foreign minister has said the UN Security Council should consider military action in Syria if an international peace plan fails to stop the violence under President Bashar al-Assad's government.
Alain Juppe also demanded on Wednesday that 300 UN observers authorised to go to Syria be deployed within 15 days. He said Paris would consider peace envoy Kofi Annan's scheduled report on May 5 as a deadline for Damascus to comply with the plan.
"We think this mediation should be given a chance, on the condition that the deployment of the observer mission happens quickly,'' Juppe said after a meeting with Syrian dissidents at his ministry.
Bernard Valero, spokesperson for French foreign ministry, speaks to Al Jazeera
The plan isn't dead, he added, but "it is severely compromised".
Juppe said that Annan's report on May 5 on the state of the UN-backed ceasefire will be "a moment of truth: Either this mediation is working, or it isn't''.
He claimed that Assad's government has not honoured the pledges to withdraw its military from cities and towns.
"We cannot allow ourselves to be defied by the current regime,'' Juppe said.
Juppe said France has been discussing with other world powers the prospect of invoking Chapter 7 of the UN Charter, which allows for action that could be militarily enforceable.
His comments come as activists reported on Wednesday the deaths of scores in renewed violence across the country.
The Local Co-ordination Committees (LCC), an opposition activist network, said security forces fired rockets that ripped through a building in Hama district of Mashaa al-Teran, killing at least 54 people and wounding dozens more.
The central city of Hama, a centre of revolt in the year-long uprising against Assad, is hosting a small team of UN observers.
The LCC also said Syrian forces launched a second day of attacks on the Damascus suburb of Douma, despite recent visits to the town by UN ceasefire monitors.
Amateur video released from Douma showed rubble-filled streets with scorched storefronts and burned out vehicles after the reported shelling attacks.
In the northwestern province of Idlib, activists said four civilians were killed as security forces shot on a bus at a checkpoint on the main road from Aleppo to the capital.
On Tuesday, Annan told the Security Council that Syria had failed to withdraw weapons from population centres in violation of the terms of the April 12 truce.
"The situation in Syria continues to be unacceptable," he said.
"The Syria authorities must implement their commitments in full and a cessation of violation in all its forms must be respected by all parties."
Annan also noted reports that security forces were targeting people who had met members of the UN monitoring mission, which is meant to end a conflict in which left thousands of people killed.
"If confirmed, this is totally unacceptable and reprehensible," Annan said.
Annan also said he was worried about reports of fighting in areas where the advance team of monitors had not been present, including Idlib and Deraa.
In-depth coverage of escalating violence across Syria
Speaking to the 15-nation Security Council, Annan stressed the need to get "eyes and ears on the ground", although so far there are only 11 unarmed monitors in Syria out of a planned final team of 300 to be deployed under the UN Supervision Mission in Syria (UNSMIS).
Activists say even the minimal UNSMIS presence has led to a drop in the daily death toll, but UN peacekeeping chief Herve Ladsous said it would take a month to deploy the first 100 monitors.
The UN timeline has drawn derision from some Syrians.
"It takes them a month to arrive? Are they coming on horses?" asked a resident of Homs, a city that has endured sustained army shelling.
Amateur videographers have filmed the small teams of monitors traveling in their distinctive blue UN helmets and bullet-proof vests meeting rebels and residents of shelled neighbourhoods in towns and cities across the country.
Speaking after the UN under-secretary briefed the UN council, United States Ambassador Susan Rice said Ladsous told the panel that Damascus was putting restrictions on the deployment of monitors.
"Mr Ladsous reported that the Syrian government has refused at least one observer based on his nationality, and that Syrian authorities have stated they will not accept UNSMIS staff members from any nations that are members of the 'Friends of Democratic Syria'," Rice told reporters.
The 14-country group includes the US, Britain, France, Saudi Arabia, Turkey and Qatar, all of which have said Assad has lost his legitimacy because of his 13-month crackdown on opposition.