The Pakistani leader appeared to exonerate Omar Sheikh in his book In the Line of Fire, serialised this week in The Times. Sheikh, 32, who was brought up in Wanstead, East London, has been on death row since 2003 after being convicted of orchestrating the kidnap and murder of the Wall Street Journal reporter.

General Musharraf appears to have changed his mind about the Briton’s guilt, saying he now believes that the man who beheaded the American hostage was Khalid Sheikh Mohammed, the mastermind of the 9/11 attacks. This allegation has stunned Pakistani officials, who had implored their President not to disclose secrets about their investigations into al-Qaeda. Rai Bashir, Sheikh’s lawyer, said yesterday that he intended to use the memoir to force a new appeal hearing.

In the Times extract General Musharraf appears to contradict the original claim that the British militant callously planned Mr Pearl’s murder, saying: “Only later did I realise that Omar Sheikh had panicked because the situation had spiralled out of his control.” Mr Bashir said: “After reading the book, if I feel necessary, I will quote the book in my arguments in favour of my client. It can be used as evidence.” Three other men jailed for life for their part in the crime have lodged appeals.

While General Musharraf has included sensational revelations about Pakistan’s role in the War on Terror, British security chiefs believe that he has not told them everything his country’s intelligence services have discovered about plots involving British terrorists, including the July 7 suicide bombers in London. In another extract carried by The Times, General Musharraf criticised British intelligence agencies for not sharing information with him.

Allegations made in the book have upset the White House, the CIA and the Indian Government, and yesterday President Karzai of Afghanistan found himself on the receiving end of the general’s criticisms. The general claimed that the Afghan leader did not know how to combat al-Qaeda and its Taleban allies and that intelligence passed to Pakistan was useless. Mr Karzai retaliated yesterday by producing damning evidence to the White House about how the Taleban were operating unmolested in Pakistan.

The two leaders are due to meet today with President Bush. General Musharraf has admitted that his closest aides urged him not to produce such a candid memoir. “Most of the people were against my writing this book at this moment, but like a good military leader I took the decision against the major part of their advice,” he said at the launch of the book in New York on Monday.

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