For decades, she was one of Tony Blair’s most trusted – and most discreet – courtiers.

Now, for the first time, Anji Hunter, who has known the former prime minister since 1970 and was his “gatekeeper” for nearly two decades, has allowed her political insights to be made public.

Her closeness to Blair, and opinions of other members of the new Labour project including Gordon Brown and Alastair Campbell, are revealed in notes made after an off-the-record lunch with Hugo Young, the Guardian political columnist who died five years ago. “He [Blair] needs people – so do all politicians – with whom they can comfortably talk. She was his person,” Young writes.

The notes of Hunter’s insights, sometimes sharp, sometimes trenchant, occasionally wrong, are included in a new book, The Hugo Young Papers, which has been published posthumously.

Young took Hunter to lunch in February 2002 at L’Escargot restaurant in Soho, central London. She had recently joined BP after leaving Downing Street. As with other political figures he interviewed, chatted to or dined with, Young afterwards wrote up his own thoughts, together with their words.

The notes show Hunter’s fierce belief in Blair, whom she first met when she was just 15.

Young remembers her telling him at the lunch: “Tony has a terribly high view of his own probity. He is very, very honest. It’s the religious thing, in part.”

Blair, who spoke to Hunter before the lunch, was being accused at the time of intervening improperly with the Romanian government over the purchase of a steel mill by Lakshmi Mittal, a Labour donor.

The notes also detail Hunter’s views on the “very, very deep and strange relationship” between Blair and Brown, one of “total mutual dependence”.

She considered Brown “a typical son of the manse – very tight, very closed in, very serious. But also very suspicious”. She added that Brown had been telling himself from the age of six that he wanted to be prime minister.

Hunter told Young, however, that Brown would be a good premier because “he would finally have made it and all the psychological barriers would have fallen away. He would finally be able to reveal himself as a rounded human being”.

Hunter, now married to Adam Boulton, political editor of Sky News, described the low opinion at Downing Street of most of the Blair cabinet. “ ‘Surrounded by pygmies’ is the cry from the hard men in No 10. I said, Alastair [Campbell]? She did not deny it.”

Hunter then talked about the only “big people” being Blair, Brown, Robin Cook, the former foreign secretary who died in 2005, and David Blunkett, former home secretary and education secretary.

Jack Straw, now justice secretary, is referred to as having “lost his confidence”.

Hunter’s decision to allow the notes to be published is in contrast to her former boss. Blair wooed Young assiduously, particularly when he was opposition leader from 1994-7, but refused to allow any of their conversations to be published.

Cherie Blair – with whom Hunter’s relations have long been turbulent – also refused to give permission, as did John Prescott.

The book publishes parts of the notes that do not betray confidences. Young writes of Cherie: “She received me in their dreary, toy-scattered quarters, wearing tracksuit trousers and a T-shirt. But made up quite a lot. Very red lips. She certainly looks better in the flesh.”

In the one meeting with Prescott described in the book, Young says his talk was “quite incessant. There’s an almost lordly quality”.

Despite her pivotal position as director of government relations, Hunter’s judgment could be flawed.

Young writes: “Would he [Blair], I asked, want to make money when he quit?

“Absolutely not, she said – bang goes a story I have been dining out on for too many years. He would not go into business, no way.”

Blair, said to be the highest-paid public speaker in the world, has made a fortune estimated at £12m since leaving office last year.

On Lord Mandelson, now business secretary, who twice had to leave the cabinet after scandals, Young writes: “Cannot come back, she thinks.”

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