NADINE Dorries’s book on the downfall of former prime minister Boris Johnson will be delayed slightly due to “the huge volume of material the author has consulted”, publisher HarperCollins has said.

The former MP’s book, titled The Plot: The Political Assassination Of Boris Johnson, had been scheduled for release on September 28, just before the Conservative Party conference.

It will now be released on November 9.

HarperCollins said that a “small delay is necessary to allow for the huge volume of material the author has consulted, the number of high-level sources spoken to, and the required legal process needed to share her story”.

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The publisher has described Dorries’s book as a “seismic, fly-on-the-wall account of how the saviour of the Conservative Party became a pariah” and will feature “unparalleled access, from multiple inside sources talking with astonishing candour”.

Dorries (below), who received £20,500 as a partial advance from HarperCollins, said: “What began as an investigation into how Boris Johnson was removed from office ultimately revealed a corruption of democracy deep at the heart of the Conservative Party and in Downing Street.

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“Secrecy, fear and the cloak of anonymity have protected those who wield power in the shadows, until now.

“It makes The House Of Cards appear tame, but this is no made-up tale, it’s for real and for the first time, their political dark arts are about to be revealed.”

The former culture secretary, a staunch ally of Johnson, finally handed in her resignation over the weekend, with a by-election now set to be scheduled for Mid Bedfordshire.

Her departure came after weeks of pressure to act on her June 9 pledge to step down with “immediate effect”, in protest at not getting a peerage in Johnson’s resignation honours list.

Her resignation came with a scathing attack on Prime Minister Rishi Sunak, claiming he presided over a “zombie Parliament”.