Howard denies that he misled the House of Commons

Speaking in the House of Commons, he said "At no time did I cross the line between what I was entitled to do and what I wasn't," Mr Howard insisted in a stout defence of his handling of the dismissal of the former Director General of Prisons.

Miss Widdecombe, he told the Commons, had made a number of allegations about his conduct as Home Secretary. "The most serious was that I misled the House. Let me state categorically that I did not."

Miss Widdecombe had disagreed with the dismissal of Mr Lewis. "She is entitled to her opinion but I believe she is wrong. Mr Howard rejected both her charge and her interpretation of the transcripts. He said, "She is perfectly entitled to disagree with my judgment. There is no basis for her attack on my integrity."

But sources close to the Prison Service Director-General Derek Lewis, sacked by Mr Howard, backed Miss Widdecombe's interpretation of events. They said a key passage in the released transcripts were powerful proof that Mr Howard did directly intervene in operational, not just policy decisions - a charge the former Home Secretary has repeatedly denied.

To the claim that his decisions were designed to further his own career, he declared to Labour jeers, "Every decision I have taken in my career in Government has been taken because I thought it was in the public interest." Earlier Mr Howard had sat stony faced as Miss Widdecombe levelled allegations, during resumed debate on the Queen's Speech, which could derail his Tory leadership bid.