Last updated at 11:16 14 September 2006

A tearful Gordon Brown has spoken at length for the first time about the death of his baby daughter four years ago.

The notoriously private Chancellor described how his first child Jennifer Jane died at ten days old from a brain haemorrhage.

The interview with Sky News shows Mr Brown has accepted that to be voted as prime minister he must open up more to the British public.

Brown: Blair is my best friend

The Chancellor, with tears welling in his eyes, said: "There is nothing worse than having a young, precious baby taken from you.

"You never come to terms with it. You always know that there's something missing. Two weeks ago she would have been going to school for the first time.

"She was unblemished by the illness that she had. She just looked beautiful"

Mr Brown's voice faltered during the interview when anchorwoman Kay Burley when she asked how he would remember Jennifer.

He said: "It's very tough for any parents faced with a loss that you never expect, that's so surprising, that you have to come to terms with."

Mr Brown said he and wife Sarah had tried to work in Jennifer's memory to help make life better for others "so some good can come out of the tragedy".

He said: "We wanted to do something to make things better for other parents who faced the same tragedy that we faced.

"It's sometimes difficult to come to terms with it. And you have got, I think, to try and do something."

Mr Brown's emotional words come as the Labour party faces a leadership contest in which he is the frontrunner.

The Chancellor also issued a gushing - and somewhat unconvincing - tribute to the Prime Minister, claiming he was "his best friend".

He said Tony Blair had acted with "a tremendous amount of ability, skill, acumen and sensitivity to what the British people want.

"Over the 23 years I have known him, this has been one of the strongest political relationships in history.

"Tony is my friend. He will always be my friend. And you build friendships but friendships have ups and downs as well.

"No chancellor has served nine years and no prime minister has had the same chancellor for nine years.

"You are bound to go through ups and downs. But the question at the end of the day is, overall, what were the results of what happened?"

Mr Brown also spoke about his leadership ambitions - and revealed that he expects Mr Blair to step down as an MP at the next election.

He said: "Really the difference between myself and Tony Blair is only this one thing, that Tony has said he wants not to stand at the next election and, therefore, feels that he wishes to do other things.

"I have decided that I want to stand at the next general election because I feel I can do something over the next few years to meet the challenges to the country."

Mr Brown admitted he had made mistakes as Chancellor, including that he may have been too cautious about spending in Labour's first years in power.

"Perhaps I was too hard. Perhaps that time when the pension did not rise fast enough," he said, referring to his decision to let the state basic pension rise by just 75p.

Twice he did not deny that he had struck a deal on the party leadership with Mr Blair at Granita restaurant in Islington in 1994.

"I don't think deals are anything that matter in politics," he said.

But he insisted there would be no deals over when Mr Blair now decides to stand down from office.

Mr Brown has won the backing of former US President Bill Clinton, who is to address Labour's conference next month.

Meanwhile, the battle for Labour's deputy leadership hotted up when it emerged Jack Straw would launch his own bid at the weekend.

Mr Straw has condemned the "blood letting" of the past week. In a separate move, Health Secretary Patricia Hewitt called for the general public to have a say in who should be Labour's next leader.