The Brexit strategy of Theresa May has put the United Kingdom's constitution in a "suicide vest" and delivered the detonator to Brussels' chief negotiator, Michel Barnier, says Boris Johnson.
The extraordinary comments of the former British Chancellor provoked an immediate reaction from the Tory critics in the last sign of the bitter conservative division on Brexit and the future leadership of the party.
Johnson launched the attack amid a greater focus on his private life after the announcement that he had separated from his wife, Marina Wheeler, and that the couple is divorcing.
The Brexiteer's latest assault on handling negotiations in Brussels will spur speculation about his own leadership ambitions.
Johnson resigned from the cabinet in opposition to the Ladies' May plan, which would see the United Kingdom remain closely aligned with EU property rules.
Writing in the mail On Sunday, he said: "At each stage of the talks so far, Brussels gets what Brussels wants.
"We have agreed on the EU timetable, we have agreed to deliver STG39 billion, in exchange for nothing.
"With the proposal of Checkers we are willing to accept their rules, forever, without being able to comment on the elaboration of those rules.
"It's a humiliation, we're like a seven-stone weakling that is comically out of shape for a 500-pound gorilla."
He also lashed out against the "backstop" of Northern Ireland, the measure aimed at ensuring that there is no hard border with Ireland.
According to the version of the EU plan, if no trade agreement with the United Kingdom solved the problem, Northern Ireland would remain part of the single market.
Johnson said: "We have opened ourselves to perpetual political blackmail, we have wrapped a suicide vest around the British constitution, and we delivered the detonator to Michel Barnier.
"We have given him a jemmy with which Brussels can choose, at any moment, to break the union between Great Britain and Northern Ireland."
The alternative support of the United Kingdom and the plan of the Checkers would mean "accepting EU rules, without being able to comment on those rules", leaving the country as a "vassal state".
He said: "We have managed to reduce the great British brexit to two terrible options: either we must divide the Union, or the whole country must accept the EU law forever."