TONY Blair will only resign early as an MP if a major international organisation such as the United Nations offers him a job too good to reject, his agent pledged last night.

John Burton's comments followed renewed speculation that Mr Blair will next Thursday quit as both Prime Minister and MP for Sedgefield, County Durham.

Downing Street moved quickly yesterday to quash the rumours about him leaving Parliament.

The rumours appear to have arisen because Mr Blair is planning to visit his constituency next Friday and he has always pledged to tell his constituents first if he were resigning as an MP.

Mr Burton said: "He has said he will tell me first and that he will only leave the constituency if he is invited to do a job of international importance, something like the United Nations.

"Otherwise, he would not want to let the people down in his constituency, because they voted for him to stay on until the next General Election."

Contrary to reports, no meeting of the Sedgefield party has been organised for next Friday at Trimdon Labour Club, although Mr Burton said it was likely one would be arranged to coincide with Mr Blair's visit.

When he does choose to leave as MP, Mr Blair will be remembered locally for his achievements in Sedgefield, Mr Burton said, with unemployment down and much better exam results at GCSE.

"All the schools have much improved, we have a new community hospital and a new science park," he said. "Sedgefield has been transformed."

He added: We've come to know him, to love him, to cherish him and we would like him to stay on for as long as possible.

At Westminster, Mr Blair's official spokesman said: "The announcement next week will be solely about the Prime Minister as leader of the Labour Party.

"He has made no decision whatsoever to stand down as an MP and very firmly remains MP for Sedgefield and proud of it.

"He is simply going to talk next week about his position as leader of the Labour Party. I have been authorised this morning to say he has made no decision whatsoever to stand down as an MP."

Former Home Secretary Charles Clarke denied yesterday that he was poised to challenge Gordon Brown for the Labour leadership.

He said reports that he had rounded up the support of 44 other Labour MPs were 'without foundation.

The Sun reported that Mr Clarke - who was sacked as Home Secretary a year ago - was ''adamant'' that he would mount a challenge.

But Mr Clarke responded: ''There is no foundation to the Sun's story today."