British Submarines Fire on Gaddafi's Forces

She told CNN that Gaddafi would face 'swift and sure consequences including military action' if he ignored international demands.

Residents in the rebel-held city of Misrata said they faced heavy shelling yesterday - denied by Gaddafi's government - another breach of the broad-ranging UN resolution.

At least 38 people are believed to have been killed in the attack in Misrata. But Gaddafi condemned the resolution. He told Al Jazeera: 'This is blatant colonialism. It does not have any justification.

'This will have serious consequences on the Mediterranean and on Europe.'

Libya's oil ministry also urged Western firms which abandoned operations in the country at the outbreak of unrest last month to return, warning that contracts may otherwise be handed over to companies from countries such as China and India.

RAF fighter jets were deploying to the Mediterranean to join the international effort to protect Libya's people from aerial assault by Gaddafi's forces.

Neither the Ministry of Defence nor Downing Street would last night confirm whether any RAF planes had set off on their mission, codenamed Operation Ellamy, or where they would be based in the Mediterranean.

Mr Cameron yesterday said that Typhoons and Tornados, together with surveillance and air-to-air refuelling craft, would be ready to leave within hours.

Gerard Araud, French ambassador to the UN, said: 'So I guess that after this summit, I think that in the coming hours, I think we will got to launch the military intervention.'

President Obama has made it clear that any military action would aim to change conditions across the whole of Libya - rather than just in the rebel-held east.

He said: 'All attacks against civilians must stop. Gaddafi must stop his troops from advancing on Benghazi, pull them back from Ajdabiya, Misrata and Zawiyah, and establish water, electricity and gas supplies to all areas.

'Humanitarian assistance must be allowed to reach the people of Libya.

'Let me be clear, these terms are not negotiable. If Gaddafi does not comply... the resolution will be enforced through military action.'