BENGHAZI: Libya on Saturday accused rebels of breaching a truce as insurgents mobilised to defend their stronghold of Benghazi and a French diplomat said Western military intervention was imminent.

US President Barack Obama, meanwhile, delivered a blunt ultimatum to Libyan leader Moamer Qadhafi, threatening military action if he ignored non-negotiable UN demands for a ceasefire and a retreat from rebel bastions.

Washington also accused the Qadhafi regime of violating the truce.

But Libyan Deputy Foreign Minister Khaled Kaaim early Saturday accused rebels of breaching Tripoli’s self-declared ceasefire. He earlier said the Libyan military will not attack Benghazi, which has a one-million population.

“Armed militias have begun firing a few minutes ago in the town of Al Magrun,” about 80 kilometers south of Benghazi, he told reporters. “The bombing is continuing.”

Kaaim said the government forces were “not taking any action against them because we don’t want to violate the ceasefire.”

A loud explosion and anti-aircraft fire was heard late on Friday in the city, AFP correspondents said, though the cause was not immediately known.

With the city on tenterhooks for a second straight night, the rebel military command urged its fighters to mobilise swiftly to defend western access routes to Benghazi, in a statement read on rebel radio.

France on Saturday will host what it said would be a “decisive” summit with the European Union, Arab League and African Union, as well as UN chief Ban Ki-moon, on taking UN-sanctioned military action in Libya.

France’s Ambassador to the UN, Gerard Araud, said he expected military intervention within hours of the summit.

“The US, the UK and France, we have also launched the ultimatum about the ceasefire, we have set the conditions,” he told BBC television.

“So I guess that after the summit, I think that in the coming hours, I think we will go to launch the military intervention.”

Obama warned Qadhafi of “consequences” if he did not comply with the Security Council resolution passed on Thursday and evoked “military action” if he failed to do so.

“Qadhafi must stop his troops from advancing on Benghazi, pull them back from (the cities of) Ajdabiya, Misrata and Zawiyah and establish water, electricity and gas supplies to all areas.”

Resolution 1973 authorises “all necessary measures” to establish a no-fly zone, protect civilian areas and impose a ceasefire on Qadhafi’s military which has battled for the past month to crush an armed revolt.

It “demands the immediate establishment of a ceasefire and a complete end to violence and all attacks against, and abuses of, civilians.” Obama said he would deploy US forces to support a no-fly zone against Libya, but left uncertain the full scope of American military involvement in any action.

Earlier, Libyan Foreign Minister Mussa Kussa said Tripoli had “decided an immediate ceasefire and an immediate halt to all military operations” because, as a UN member, it is “obliged to accept” Security Council resolutions.”

This came despite remarks by Qadhafi on Thursday that the council had “no mandate” for such a resolution, “which we absolutely do not recognise.”

But rebel military council official Khaled al-Sayeh told reporters in Benghazi that the “Qadhafi regime never stopped firing or attacking people.

Until this moment he is still attacking places under siege.” He said there had been “sustained shelling” in Zintan, Ajdabiya and Misrata on Friday.

The rebels also said they were coordinating with Western nations on targets for air strikes against Qadhafi’s forces, as a coalition of countries geared up to launch attacks under the Security Council resolution.

So far Belgium, Britain, Canada, Denmark, France, Italy, Norway, Qatar, Spain, Sweden and the United States have said they will help to implement the no-fly zone.

French Foreign Minister Alain Juppe said “everything is ready” to intervene in Libya, but he refused to give a timetable.

British Prime Minister David Cameron said London would deploy Tornado and Typhoon warplanes as well as air-to-air refuelling and surveillance aircraft to airbases “from where they can take the necessary action.”

The United Nations has estimated more than 1,000 people have been killed in the month-long uprising after Qadhafi’s rule.

Some 300,000 people have already fled Libya since the rebellion began and many more are expected to leave if full-blown war breaks out, the agencies said.

Elsewhere in the Middle East, four protesters were killed by security forces in the Syrian city of Daraa, south of Damascus, and hundreds wounded, a human rights activist contacted by AFP said.

In Yemen, President Ali Abdullah Saleh announced a state of emergency after medics said 46 people were killed when regime loyalists and police opened fire on protesters demanding his ouster in Sanaa.