Retreat now or bombing will begin, Gaddafi is warned

The international community reacted with deep scepticism last night to the Libyan regime's suggestion that forces loyal to Muammar Gaddafi would enact an immediate ceasefire in the face of the threat of military intervention.

The subdued announcement by the Libyan Foreign Minister Moussa Koussa of an "immediate ceasefire" came little more than 12 hours after the UN Security Council had wrong-footed the regime by announcing air strikes to enforce a "no-fly zone" with the aim of halting assaults on Benghazi and Tobruk.

But in Western capitals, as among rebel forces within Libya, the claim was met with disbelief. David Cameron told the BBC that the regime's words meant little. The Libyan leader "must stop what he is doing, brutalising his people", he added. "If not, all necessary measures can follow to make him stop." He added: "We will judge him by his actions – not his words." Mr Cameron had earlier told the Commons that the RAF had made preparations to deploy warplanes in "the coming hours" to "air bases from where they can take the necessary action".

Barack Obama spoke last night in terms that suggested that the US did not accept a ceasefire had been enacted. He told Colonel Gaddafi that a comprehensive ceasefire meeting the conditions laid out in the UN resolution would mean withdrawing from key frontline towns, including Misrata and Ajdabiya. He went on: "That means all attacks against civilians must stop. Gaddafi must stop his troops from advancing." The terms, he said, were "not negotiable".

A spokesman for the foreign ministry in France, which co-sponsored Thursday night's resolution with Lebanon and the UK, said: "Colonel Gaddafi begins to be afraid, but on the ground, the threat hasn't changed. We have to be very cautious."

One of Col Gaddafi's sons, Saadi, insisted yesterday that his father was open to the requirements of the US President. "The key thing is the speech of Obama " he said. "He [Gaddafi] is very comfortable and will co-operate."

At least on the surface, the normally pugnacious Mr Koussa was somewhat chastened by the strong words from abroad. The minister, who read and at times mumbled his words before hastening away without taking questions, spoke in the starkest contrast with the tone adopted by Gaddafi on Thursday before the UN vote, when he promised to hunt down rebels who refused to surrender "house by house, room by room", adding later: "The world is crazy and we will be crazy, too."

But the rebel leadership, fighters on the ground and many residents of "Free Libya" pointed out offensive action by Gaddafi's forces had continued for hours after the announcement was made in Tripoli. Mustafa Gheriani, an opposition spokesman in Benghazi, said: "He has been bombing Ajdabiya, he has been bombing Misrata from this morning. How can you trust him? He has shown no signs that he is prepared to abide by his own ceasefire." At a checkpoint at Sultan, 60 miles west of Benghazi, Abdullah Fasar, a militia commander, laughed. "Are we imagining the firing coming towards us?" he asked.

The National Council, as the provisional government is called, is expected to hold a meeting tonight in response to the day's events. As well as military options, they are due to ask Western powers to provide humanitarian aid.

With reporters prevented from driving any distance from Tripoli it was impossible to establish if the ceasefire had halted the regime's fierce assault on the besieged Misrata, the rebels' most westerly coastal stronghold. But if substantiated, the bloodshed there was the gravest ceasefire violation, with a doctor telling Reuters that 38 people had died in what residents said was indiscriminate shelling during and after heavy fighting that lasted from early morning through most of the afternoon. Khaled Kaim, Libya's deputy foreign minister, insisted last night in Tripoli: "The cease-fire for us means no military operations whatsoever." But the news agency also quoted an unnamed National Security official in Washington as saying there was confirmation that shelling had continued beyond the ceasefire call.

A doctor said the blockade of the city had stopped aid ships. "We have had to perform surgeries in the hallways using the light from our cell phones," he said.

Unconfirmed reports from Tajura, a suburb east of Tripoli, said that for the second week running a protest after Friday prayers had been halted by troops firing over protesters. Journalists were taken to the UN building inTripoli. They were confronted by flag-waving Gaddafi supporters chanting: "Down with the Resolution!" One said that while the Libyan rebels had been armed, "Bahrain's government attacked peaceful protesters. Why did the world not interfere with that?" Police chief Colonel Mohammed Abdel Salam insisted that while the ceasefire resolution meant the cessation of army activity, he believed Benghazi and Tobruk would revert to regime rule and that "the people" would win.

Government spokesman Moussa Ibrahim said the regime had invited Malta and Turkey to provide emissaries to implement and monitor the ceasefire. Mr Koussa said it was "strange and unreasonable" that the UN had authorised force against Libya. Later on, Germany and China were also invited.

US Secretary of State Hillary Clinton said the ultimate goal of the action "would have to be the decision by Gaddafi to leave".