Gaddafi is isolated claim diplomats

British diplomats have insisted it is a matter of "when, not if" Muammar Gaddafi will go as Nato marks 100 days of air strikes against his Libyan regime.

A senior Foreign and Commonwealth Office official claimed the momentum had "shifted irrevocably" against the dictator and he was down to a "handful" of followers.

"The sands of time are running down for Gaddafi," he told reporters in London.

Nato has now flown 12,000 sorties, including 5,000 attack missions, and hit more than 2,400 targets since launching strikes against Libya 100 days ago on Sunday under a United Nations mandate to protect civilians.

The British military alone has damaged or destroyed more than 500 targets, including 240 tanks, armoured vehicles, artillery and rocket launchers, and more than 150 buildings, including bunkers and ammunition stores.

The Ministry of Defence revealed yesterday that the UK's part in the Nato operation is costing taxpayers 43 million per month.

The senior British diplomat said it was "clear" Gaddafi was isolated within Libya and pointed to the "steady stream" of defectors, including ambassadors, ministers and military officers, among them five generals who fled the country last month.

"The momentum has shifted irrevocably against Gaddafi and those around him," he said.

"Gaddafi's actions have stripped him of legitimacy. There can be no future for Libya with him in power."

He added: "The anger against him is simmering. The question is not if he will go, but when."

International attention is now turning to what will happen in Libya if and when Gaddafi's regime falls.

A UK-led International Stabilisation Response Team has been in the rebel-held city of Benghazi for most of the past month discussing with the opposition National Transitional Council (NTC) how the country should be run.

"The NTC and we are planning carefully and comprehensively for the days, weeks and months after Gaddafi has gone," the British diplomat said.

The Nato mission suffered a setback last weekend when a missile strike in a residential area of the capital Tripoli resulted in civilian deaths, something commanders blamed on a "weapons system failure".

Senior British military spokesman Major General Nick Pope said RAF pilots have twice in the past 10 days diverted laser-guided bombs away from their targets at the last second after spotting people who might be civilians in the area.