The document, leaked to the 'The Sunday Times by a Conservative party source, contains a catalogue of explosive allegations about Johnson's sexual liaisons and damning assessments of his character.
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The 4,000-word so-called "war book" emerged as Johnson and his Indian-origin wife Marina Wheeler announced earlier this week that they were to divorce and was allegedly prepared during the post-Brexit referendum Conservative party leadership election in 2016 but shelved as Johnson withdrew from the race to make way for Theresa May as party leader.
The dossier accuses Johnson of "lying" about his affair with the socialite Petronella Wyatt, who had to abort his child, and claims he had an affair with the journalist Anna Fazackerley "on one occasion visiting both her and Petronella Wyatt on the same night".
A senior Conservtive party member who received the paper last week told the newspaper, "This was put together by May's team to smear Boris. It's their 'war book' on him".
Downing Street and Conservative Campaign Headquarters (CCHQ) categorically denied circulating the document or ordering any updating of the dossier.
"It is genuinely offensive and categorically untrue that we have done anything to update this document. The suggestion that this was circulated, updated or briefed in any way by CCHQ or No 10 is a lie," a senior aide to Prime Mimister May said.
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The latest controversy, which comes days before the Conservative party conference where May is expected to go head to head with Johnson, came as the former Cabinet minister fired a new round in his war over Brexit with the British Prime Minister when he claimed that her Brexit strategy had strapped a "suicide vest" around the UK Constitution and handed the detonator to Brussels in a newspaper column.
"I think there are much better ways to articulate your differences," UK home secretary Sajid Javid said in reference to the remark.
"It's a reminder for all of us in public policy, whichever party we represent, to use measured language because I think that's what the public want to see," he said.
Hardline Brexiteer Johnson, who quit as foreign secretary in July in protest at May's Chequers proposals for Britain's future relationship with the European Union (EU), was also rebuked by housing minister James Brokenshire for his latest attack.
"I think he is wrong on this, I think the tone that he has used isn't right. I think that we just need to be very focused on actually moving forward with the Chequers plan," Brokenshire said.
Other senior Tories were more vocal, with Alan Duncan, a junior Foreign Office minister, tweeting: "For Boris to say that the PM's view is like that of a suicide bomber is too much. This marks one of the most disgusting moments in modern British politics".
"I'm sorry, but this is the political end of Boris Johnson. If it isn't now, I will make sure it is later," Duncan tweeted.
Another foreign office minister Alistair Burt said that the analogy was "outrageous, inappropriate and hurtful".