Tony Blair, who as prime minister led Britain into wars in Afghanistan and Iraq, announced yesterday that he will give all the profits of his upcoming biography to help fund a rehabilitation centre for injured soldiers.

The former prime minister's £4 million advance, plus all future royalties, will be donated to the Royal British Legion, which is building a sports centre for wounded personnel.

It is the single largest donation received by the Legion in its 89 years as a charity for Britain's armed forces. In a short statement announcing the donation, Mr Blair's office said yesterday that he was motivated by a desire to honour the “courage and sacrifice” shown by British troops. But the donation received criticism from anti-war activists, some soldiers and a number of families who lost loved ones in Iraq and Afghanistan with them accusing Mr Blair of using his donation to assuage guilt over taking Britain into a highly unpopular war in Iraq.

Other critics also pointed out that none of the profits from the book would go to charities in Afghanistan or Iraq where hundreds of thousands of civilians have been wounded.

The book will be published on September 1 and is one of the most anticipated political memoirs of recent years. It is also an opportunity for Mr Blair to influence the historical debate on his 10-year premiership which came to be dominated by the controversy decision to commit British troops in Iraq. The final size of his donation will depend on book sales but it is thought that it will be at least £6m — even though Mr Blair has had to pay back an undisclosed portion of his advance because he chose not to serialise the book.

His office would not confirm whether the Royal British Legion were approached before or after the former prime minister's appearance at the Chilcot Inquiry in January where he remained defiant over Iraq and said he had “no regrets” in removing Saddam Hussein. “The decision was made a long time ago,” he said. “A number of different charities were suggested and he chose the Royal British Legion.”

Chris Simpkins, director general of the Royal British legion, said the money would be put towards the £12m they need to raise to build the Battle Back Challenge Centre — a rehabilitation sports complex for wounded soldiers.

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