Cherie Blair is sitting on a sofa texting when I arrive and while she chirps a cheery greeting, she doesn’t look up. This gives me ample time to observe the cream and black Paddy Campbell suit, the double strand of pearls, her porcelain skin and the softly coiffed chestnut hair. The effect is elegant, safe and a little staid. Then she turns her gaze on me and the result is startling. Those big, baby-animal eyes, the letterbox smile and the malleable — almost rubber — quality of her lower face make her look momentarily like a Spitting Image caricature.

The slightly manic expression settles and she becomes a smiley, middle-aged lady, complimenting me on an old dress, offering to sign my copy of her autobiography, asking about the weather in Scotland and remarking on sunny days in Argyllshire at Derry Irvine’s pad.

Outside, half a mile away from her publicist’s central London office, her husband Tony is sitting in their £3.65m (give or take a recessionary £100,000 or so) Connaught Square home working on his £5m memoirs and the Labour party he once led is in meltdown. The home secretary has already fallen, Hazel Blears’s resignation is happening as we speak and the nightmare that is the election result is on its way.

Blair is remarkably sanguine about what could be the death-throes of a regime which she helped to implement. Her autobiography Speaking For Myself is out in paperback and she will promote it at the Edinburgh Book Festival this summer where she is the Sunday Times guest speaker. The book makes it clear that, like Lady Macbeth, she gave her husband no peace until he agreed to seize the crown and stand for the party leadership.

“Of course, of course,” she says when I ask if the Labour party can recover from its present troubles. “In the end we need politics and we need politicians. It’s up and down, rough and tumble. The principles and the political outlook that the Labour party represents are an important part of our society.”

She could be forgiven a degree of schadenfreude. Her well-documented antipathy to Gordon Brown surfaced long before the leadership challenge. The stoker of her husband’s political ambition, she believed that “Tony was being taken for a ride by Gordon” almost as soon as they started sharing an office together as rookie MPs in 1987. The worse it gets for Brown now, the better the Blair years appear in retrospect, or so the thinking goes. His wife is of the firm belief that her husband’s premiership is on a par with Winston Churchill’s. “He was fantastic. I’m sure history will judge him very well. I think he’ll be up there with Churchill,” she told Vanity Fair magazine.

Now breathing the rarefied air of consort to a global statesman, she is keen to distance herself from the grubby, knife-wielding end of British politics. She says of the book: “I wanted it to be a woman’s story,” she says. “It’s not a political book. My husband will write that one.”

There are to be no political questions for Mrs Blair (who at the age of 14 declared she would be the first female prime minister), and she will certainly not be saying anything about expenses.

The ever so bright, slightly gobby girl from the wrong side of the Liverpudlian tracks is these days far too busy championing the rights of women around the world, helping Rwanda re-establish its legal system in the wake of the genocide and acting as patron to no end of good causes, to share her thoughts on the carnage in the cabinet.

She must, however, have an inkling of who she would like to see succeed Brown as party leader. Blair’s laughter, long and hard, does not sound at all forced.

“At the moment Gordon is . . . I mean this is a really difficult time for him,” she says. “I’ve been in Number 10 so I know what it’s like. I’m just really glad that he has Sarah and the children to give him support, which I’m sure they do.”

Since the publication of her autobiography a year ago, Blair has been hard at work promoting the book abroad. There have been trips to the US, Australia, Italy, Holland and Norway. In August it comes out in Chinese — “ a surreal experience” — and she will be attending the Shanghai Book Festival.

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