Boris Johnson '˜suicide vest' jibe '˜spot on': Sammy Wilson

Sammy Wilson said the former foreign secretary’s assessment of the Brexit plan “communicated beautifully the dilemma the government has placed the country in”.

Writing in the Mail on Sunday, Mr Johnson lashed out at the government’s ‘backstop’ measure, which aims to ensure there is no hard border with the Republic in the event of a no-deal withdrawal from the EU.

The ex-Cabinet minister said: “We have opened ourselves to perpetual political blackmail. We have wrapped a suicide vest around the British constitution - and handed the detonator to Michel Barnier.

“We have given him a jemmy with which Brussels can choose - at any time - to crack apart the union between Great Britain and Northern Ireland.”

While the remarks have provoked a backlash from some Tory critics – with one minister branding them “one of the most disgusting moments in modern British politics” – Mr Wilson said he had “hit the nail on the head”.

He told the News Letter: “Boris is spot on with his analysis and I support him 100%. He has graphically portrayed the folly of the government’s position at present and the danger of the EU’s demands.”

Mr Johnson claimed the backstop and the Chequers plan would both mean “agreeing to take EU rules, with no say on those rules”, leaving the country a “vassal state”.

He said: “We have managed to reduce the great British Brexit to two appalling options: either we must divide the Union, or the whole country must accept EU law forever.”

Mr Wilson, who previously said Mrs May’s Brexit strategy was “flawed and weak-kneed”, yesterday labelled the backstop as a “constitutional time bomb”.

He added: “There is no need for it. In fact it represents an incentive for the EU not to reach a deal with the UK, because it either means that the government must tie all of the UK to EU rules or else agree to the breakup of the UK, neither of which are acceptable.”

When asked if he took issue with Mr Johnson likening the Brexit strategy to a “suicide vest”, Mr Wilson told the News Letter: “The language used by Mr Johnson is not offensive at all.”

Mr Johnson’s comments drew a furious response from Tory MP and ex-army officer Tom Tugendhat - who has been viewed as a possible rival in a leadership contest.

“A suicide bomber murdered many in the courtyard of my office in Helmand,” he said. “Comparing the PM to that isn’t funny.”

One senior minister said the comments marked the “political end” of the former foreign secretary.

Mr Johnson launched the attack amid further focus on his private life after it emerged that he and his wife Marina Wheeler are divorcing.

His latest assault on Mrs May’s handling of negotiations with Brussels will fuel speculation about his own leadership ambitions.