Blair believes Saville was worth it

He also pays tribute to Nobel laureate John Hume, describing him as a "genuine Titan" and praising his committment to the peace process.

Mr Blair devotes a large section of his memoirs to his involvement in the peace process and his dealings with the key political figures. He also discusses his decision in 1998 to give the green light to the Saville Inquiry into the events of Bloody Sunday.

Paying tribute to Mr Hume, the former Prime Minster says: "John Hume was, is, a great political figure and genuine Titan. He has vision and imagination and foresight when others were resolutely still in blinkers."

The book contains Mr Blair's first public comments on the Saville Inquiry since its findings were published in June. "Until it reported in 2010, I considered it a classic example of why you should never conduct inquiries into anything unless utterly impossible to resist, or in the most truly exceptional circumstances.

"However, the report, when published, proved me wrong. It has been worth it; an exhaustive and fair account of what happened," he said.

Elsewhere in the book, Mr Blair admits that he "stretched the truth past breaking point in order to get agreement" during the peace process.

Foyle MP Mark Durkan says it was difficult to trust the former prime minister. "Tony Blair knew that I didn't believe a lot of what he told me at the time. He didn't like it when you told him you didn't necessarily believe any of it," he said.