A FORMER close friend and lover of Boris Johnson has turned against him over his plan to rip up part of the Brexit Withdrawal Agreement.

Petronella Wyatt, who writes for the Spectator magazine, which Johnson used to edit, vented her anger on Johnson in a series of tweets this afternoon, comparing him unfavourably with Nicola Sturgeon.

"This is the first time a British Government has knowingly and with relish ignored international law. Boris is swerving all over the road with this country's reputation. He is turning the UK into a morally bankrupt gangster state. Even Blair never did this," she wrote.

"We have a PM who is busking it. A few weeks ago he said we would be back to normal by Christmas. Now it's cancelled. At least Sturgeon is consistent."

She added: "This is not government by any understanding of the term."

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Johnson was sacked from his shadow cabinet role in 2004 by the then Tory leader Michael Howard following claims Johnson lied about the affair with Wyatt.

Howard "relieved him of his responsibilities" within two hours of learning of renewed allegations about Johnson's relationship with the columnist and socialite.

Senior Tories backed Howard's decision, emphasising that Johnson had not been sacked for his alleged liaison but for a lack of candour.

When claims of the affair with Wyatt originally surfaced, Johnson, who was at the time married with four children, dismissed them, saying: "I have not had an affair with Petronella. It is complete balderdash. It is an inverted pyramid of piffle. It is all completely untrue and ludicrous conjecture."

But his position became untenable when a newspaper later published claims from Wyatt’s mother that her daughter had become pregnant by Johnson and had an abortion.

Theresa May, the then shadow Secretary of State for the Family, supported his sacking, saying he had denied stories which now appeared to be true.

The claims of an affair capped an uncomfortable period for Johnson in which he was ordered to visit Liverpool to apologise for a Spectator editorial which accused Liverpudlians of wallowing in grief over the murder of the British hostage Ken Bigley.

In 2016 Wyatt spoke highly of Johnson, then London mayor, comparing him to his hero Winston Churchill.

The Times reported that Wyatt conducted a four-year affair with Johnson in the early 2000s that ended with her terminating a pregnancy.

"Let me say at this point that Boris never sets out to lie," Wyatt wrote in 2016 a newspaper article. "It is just that he will do anything to avoid an argument, which leads to a degree of duplicity. He will twiddle with his pencil or look at his feet rather than utter a word that would involve himself in an unpleasant confrontation. His untruths are generally harmless and get him into more trouble than the person he directs them at."

Johnson's marriage to Marina Wheeler survived the affair, but later broke down.

Wyatt and Johnson met in the early 1990s while working at The Daily Telegraph.

They met again in 1999, when he was appointed editor of The Spectator, of which she was deputy editor, and began their affair the next year.