Dame Annette King lifts the lid on her political career in new book

The woman described as "the mother of the Labour Party" and New Zealand's longest-serving female MP has been honoured with her very own book.

A biography of Dame Annette King is released today, lifting the lid on her 30 years in - and out - of the halls of power.

Dame Annette says of all her plans after leaving Parliament, a book was not one of them.

"I don't think I'd have ever got around to an autobiography," she told Newshub.

"And I sometimes think I've got political selective memory, so I don't always remember things the same way as others do."

Co-authored by her former press secretary John Harvey and NBR political journalist Brent Edwards, Dame Annette's biography goes from her childhood, through the Lange, Clark and Key years - all the way up to stepping down as deputy Labour leader, and out of Parliament.

Interviews with figures such as Dame Fran Wilde, Trevor Mallard, and Jacinda Ardern fill in the gaps, positive and negative.

"Annette remembers everything. And Annette especially remembers if you cross her!" the Prime Minister told guests at the book's launch party in Wellington.

One person not interviewed is David Cunliffe, whose tenure as Labour leader does not come across favourably in the book - and not just by Dame Annette.

"David's got his strengths, but one of them was not being leader of the Labour Party - and one thing I do highlight in the book is I think the best people to decide who a leader is are the caucus members," she says.

Dame Annette says the book has 'warts-and-all' coverage, and doesn't shy away from anything that might have hurt her or made her look bad.

"I don't resile from what's in the book, and other people's words are their words. I didn't edit what they said, or say 'you can't have that in the book!'"

Dame Annette now serves as New Zealand's High Commissioner to Australia, so won't experience seeing her face all over bookshop shelves.

"I'm heading back to Canberra on Saturday, so I won't have to see it but I did say to John [Harvey, one of the co-authors], 'I don't know whether I like that photograph' and he said 'you were always vain!'"

But she says the Christmas present for all her family is already sorted.

Annette King: the Authorised Biography is out today via Upstart Press.