Gordon Brown has said the supposed crunch talks at a restaurant with Tony Blair over the leadership of the Labour Party was just a rubber-stamping exercise.

The former prime minister and chancellor said “The Deal” widely believed to have been struck in Granita was the result of negotiations which had been worked through weeks before.

He said Mr Blair had offered him control over economic and social policy as shadow chancellor and promised that if elected, he would stand down in second term, paving the way for Mr Brown to become prime minister.

The pact made in 1994 is said to have meant Mr Blair would step aside so he could focus on family life.

“He said this was a family choice that he had already made," Mr Brown said.

"He wanted to be free from day-to-day politics to be with his children in their teens – the time of life when parents are most needed. It was a promise he repeated on several occasions."

He added: “I always smile when commentators write that we hammered out a deal in the restaurant. The Granita discussion merely confirmed what he had already offered and I had already agreed.

“The only new point was Tony’s overture that he wanted to show that, unlike the Tories under Mrs Thatcher, Labour was not a one-person band but a partnership.

“As we walked out of the restaurant towards his home, he emphasised the word ‘partnership’ again and again, telling me it represented a new departure for British politics.”

Writing in his latest book My Life, Our Times, to be released on Tuesday, he details the arrangements and how his brother Andrew had recorded the sequence of events in his diary.

His brother’s diary includes extracts which say Mr Blair described the then-shadow chancellor as the “greatest political mind the Labour Party has had”.

Speaking about the deal made with Mr Blair, Mr Brown said: “I would accept his assurances. He would give me control of economic and social policy and would stand down during a second term.

“Unwilling to see the party divided in a way that would endanger the prospects for reform, in the days leading up to May 30 I informed those closest to me of my intention not to stand.

“The rest was a formality. On May 31, I sat down again with Tony near his home in London, at a restaurant called Granita.”

However, he claims the relationship got off to a bad start following the meeting.

He added: “When I offered to chair Tony’s leadership campaign, he demurred. And while I helped write his leadership speeches, I was frozen out of the campaign.

“Long into the future, the focus of the 1994 leadership race would wrongly remain on what was said at Granita.

“The restaurant did not survive and ultimately neither did our agreement.”

In his diaries, Mr Brown also claimed that the UK was "misled" over Saddam Hussein’s weapons of mass destruction and the Iraq War was unjustified.

The former prime minister, who was chancellor when the decision to go to war in 2003 was made, revealed top-secret US intelligence casting serious doubt over the dictator’s destructive capabilities was not shared with Britain.

He claimed only after leaving office did he become aware of “crucial” papers held by the US Department of Defence and believes the course of history could have been different had the information been shared.

Mr Brown said: “If I am right that somewhere within the American system the truth about Iraq’s lack of weapons was known, then we were not just misinformed but misled on the critical issue of WMDs."