In a major address to the US people President Obama defended the Allies’ military action in Libya was “necessary” but also insisted US involvement in Libya will be limited.

The speech came as anti-Gaddafi rebels pushed towards Colonel Gaddafi’s hometown of Sirte, 285 miles east of the capital, Tripoli.

Clarifying the US’s position Obama said they wanted Gaddafi gone but regime change was not the purpose of the operation which had so far saved “countless lives”.

The US hope that the Libyans will overthrow the dictator themselves and that the combination of military action and political pressure will help bring this about.

According to a US official there are signs that Gaddafi’s closest supporters are beginning to desert him. “It’s too soon to tell where things are headed, but morale doesn’t seem to be high among senior regime officials,” the official told the BBC.

Since the Allies began airstrikes against Gaddafi’s army on March 19 the rebels have made significant gains recapturing oil installations and towns such as Ras Lanuf, Brega, Uqayla and Bin Jawad.

But the ill-equipped and inexperienced rebels face the full might of Gaddafi’s forces in the Western Libyan town of Sirte.

Meanwhile the UN, Nato, the African Union and Arab League are preparing to meet in London later today to discuss the way forward for Libya.

The US plans to hand over the operation of military action to Nato on Wednesday.

UN Approves military action

Allied airstrikes continue