Libyan leader Muammar Gaddafi has appeared on state TV and denied rumours that he had fled the chaos-stricken country.

The embattled dictator's 41-year rule is hanging in the balance amid bloody clashes between protesters and security forces.

He has said he remined in Tripoli and referred to foreign news channels who reported that he had travelled to Venezuela as "dogs".

In a brief and strange address from the passenger seat of a van clutching an umbrella he said: "I want to show that I'm in Tripoli and not in Venezuela. Do not believe the channels belonging to stray dogs. I wanted to say something to the youths at the Green Square (in Tripoli) and stay up late with them but it started raining. Thank God, it's a good thing."

With large parts of Libya already believed to be under rebel control, crowds on the streets of Tripoli have been targeted by loyalist gunmen and airstrikes.

But Mr Gaddafi's grip on power was looking increasingly shaky after a series of senior Libyan diplomats defected and spoke out against the brutal repression.

World leaders including David Cameron also intensified their criticism of the regime, demanding an end to violence estimated to have cost more than 230 lives so far.

Relatively little reliable information has been coming out of Libya, but reports suggest some elements of the army are fighting loyalist forces.

The unrest had not reached the capital until Sunday, when hundreds of protesters flooded the streets, but the situation appears to have escalated there quickly.

Justice Minister Mustapha Abdul Jalil has quit the government because of the "excessive use of violence", according to a privately owned Libyan newspaper.

The country's deputy envoy to the UN, Ibrahim Dabbashi, has also called on the dictator to step down, accusing his government of genocide.

US secretary of state Hillary Clinton said she "strongly condemned the violence in Libya", insisting: "Now is the time to stop this unacceptable bloodshed."

Mr Cameron, in Egypt on a tour of the volatile region, deployed some of the toughest language by branding the regime's actions "completely appalling and unacceptable".