Home Secretary David Blunkett last night requested an independent review of allegations that he misused his position to help a former lover.

Mr Blunkett has asked John Gieve, the Permanent Secretary at the Home Office, to appoint an independent reviewer to look into the handling of a visa application from nanny Leoncia Casalme, following allegations that he intervened in the case to help her employer, his former mistress, Kimberly Quinn.

The move followed demands from Conservatives for a judicial inquiry into the accusations, which Shadow Home Secretary David Davis said would be a resigning matter if true.

In a statement Mr Blunkett said: "Trust, plain-speaking and straight talking is something which matters so much to me as a politician and as a man that I have decided, of my own volition, to request an independent review of the allegations that I misused my position in the case of the renewal of a visa application by Leoncia Casalme."

He continued: "I regret the time and resources needed to undertake this, but in the light of the flagrant attempt to link my public position with the deeply personal circumstances of my private life, I believe that on this specific occasion, it is right to lay this accusation to rest."

Mr Davis welcomed the Home Secretary's announcement, saying: "It is the right decision, but it must be independent of the Home Office, probably a judge, who should have proper rights of access to papers and individuals."

The allegation relating to Ms Casalme's visa was the most serious in a string of claims about Mr Blunkett's behaviour made in the Sunday Telegraph yesterday

The paper quoted an e-mail from Mrs Quinn, publisher of The Spectator magazine, suggesting he fast-tracked an application by the Filipina nanny for permission to reside permanently in the UK.

Mr Blunkett strenuously denied all the allegations, insisting he had simply been asked to check a visa application form to see it was filled in correctly.

Prime Minister Tony Blair expressed his full confidence in the Home Secretary.

A statement released by 10 Downing Street read: "The Prime Minister has full confidence in David Blunkett. As last week showed, he is continuing to do a first-rate job as Home Secretary."

The Sunday Telegraph alleged that Mr Blunkett sent his official Government driver to pick up Ms Casalme's passport after Mrs Quinn sought his help in spring last year.

The 36-year-old nanny is understood to have entered the country on a short-term visa in July or August 1999. If this is correct, she would not have been eligible for a permanent visa until July 2003 at the earliest.

The paper said Mr Blunkett promised to deal with the visa problem and later told Mrs Quinn: "She would never have got it if it hadn't been for me."

But Mr Blunkett's spokes-man strongly denied the allegations.

"It's absolutely untrue that the chauffeur picked up the visa application," he said.

"It was not processed through David's office. Kimberly Quinn gave him the settlement application to ask him if it looked in good order. He said it did, and gave it back to her and it was submitted in the normal way."

Last night, a senior Home Office source said the review would focus on the question of the visa and not consider the other allegations made by the Sunday Telegraph.

But Mr Davis demanded that the review be widened to cover all the allegations made against the Home Secretary.

"The inquiry should cover all the allegations about the Home Secretary abusing his position rather than just concentrating on one specific allegation," he said.