The meeting was scheduled for Saturday afternoon at a secret location in the eastern Libyan city of Surt.

The BBC's Clarence Mitchell: "Kofi Annan's mission has run into difficulties"

But Libya's official news agency, Jana, says Colonel Gaddafi was in a desert camp outside the region and that talks instead took place between Mr Annan and the Libyan foreign minister.

In the hope of still being able to meet the colonel, Mr Annan has delayed his departure from Tripoli.

Mr Annan travelled to Libya to discuss a way of resolving the deadlock on the handover of two suspects in the 1988 Lockerbie bombing.

Two-hundred-and-seventy people died when Pan Am flight 103 was blown up over the Scottish town of Lockerbie.

Nick Pelham reports from Tripoli after being ordered off the Annan plane by Libyan authorities

Jana says any decision on surrendering the men for trial abroad will be taken, not by Colonel Gadaffi, but by the General People's Congress.

The congress is Libya's nominally top legislative and executive body and usually only meets once or twice a year.

Libyan radio says a meeting of the congress has been called for Tuesday.

In August, Britain and America offered a compromise arrangement under which the Libyan suspects would be tried in the Netherlands under Scottish law before a panel of Scottish judges in return for the lifting of UN sanctions against Libya.

Ignorance of Libyan ways

World Affairs Correspondent David Loyn says that snubbing the UN secretary-general who is making his first visit to Libya is an unusual gesture even by Colonel Gadaffi's standards.

In a commentary the official news agency says that Colonel Gadaffi is only the guide of the Libyan revolution, not the head of state. It goes on to say that those who think the colonel can sign an agreement with the UN secretary-general or anyone else, are completely ignorant of the absolute nature of people power in Libya.

The last major sticking point is Libya's desire for the two men not to serve their sentences in Britain if they're convicted. But the UK Government will not move on this and the point was made by the Foreign Secretary, Robin Cook, in a phone call to the UN secretary-general as recently as Friday.

Annan diverted

On Saturday, Mr Annan's schedule met with an unexpected interruption when his flight was re-reouted to Tripoli and journalists were taken off and he was taken on to Surt.

On his flight into Tripoli, Mr Annan told journalists that the discussions over resolving the Lockerbie dispute would be very difficult.

Fred Echkhard: "Mr Annan is hopeful of progress ..."

He said the UN had already given Libya answers to all the questions it had been seeking and that the deal was by no means sewn up.

Mr Annan said "God willing" he would be successful.

Fred Echkhard, spokesman for Mr Annan, told the BBC that the UN is "something of a middle man in this".

Dr Jim Swire: 'confident of justice', Ashoor Shamis: 'Gaddafi is sulking...'

Privately, UN officials say most of the legal details have now been resolved and that arrangements are in place for the two suspects to be transported to the Netherlands if the meeting is successful.

Dr Jim Swire, whose daughter was killed in the plane crash and has been leading the case for British families, said he was very positive about Saturday's meeting.

Key facts on Lockerbie
Profile: Muammar Gaddafi, Libyan maverick
Profile: Kofi Annan, Master of diplomacy