AMBER Rudd has denounced Boris Johnson for his “back-seat driving” on Brexit, making clear that she did not want him managing the process of Britain’s withdrawal from the European Union.

The Home Secretary, who backed Remain during the EU referendum campaign, also agreed with Ruth Davidson’s suggestion that the Foreign Secretary’s 4,000-word article on Brexit, which came as police hunted for the Parsons Green bomber and just days before Theresa May’s keynote speech on Brexit, was in appropriate and ill-timed.

Cabinet colleagues of Mr Johnson, including the Prime Minister, are said to be incensed by the Secretary of State’s intervention, which has been seen by some as, at best, pressuring Mrs May to hold to a hard Brexit and, at worst, as a bid to undermine her position and manoeuvre himself ready to put himself forward if she were to step down.

One former Tory minister said: “It is completely disgraceful. You do not write an article like that without consulting the Prime Minister and your Cabinet colleagues. It is a complete abdication of Cabinet responsibility. This is all about Mr Johnson, Mr Johnson, Mr Johnson, not about the interests of government or the country.”

A senior minister, who backed Remain, said Mr Johnson "needs to go and do something else" if he "can't settle" into his role as Foreign Secretary while a former minister said the former London Mayor was "sailing within an inch of being thrown out of the Government".

Sir Craig Oliver, David Cameron’s former communications chief, said even if the genuine intention was to support the PM, it was obvious it would be seen in Westminster as a "direct challenge".

Yet as the furore raged, Mr Johnson insisted in a tweet he was "looking forward to PM's Florence speech," declaring: "All behind Theresa for a glorious Brexit."

Appearing on the BBC’s Andrew Marr Show, Ms Rudd - who during the EU referendum campaign famously said the Foreign Secretary was not the “the man you want driving you home” after a party – hit back at her Cabinet colleague.

She said; “You could call it backseat driving, absolutely. I don't want him managing the Brexit process. What we have got is Theresa May managing that process.

“She is driving the car...and I’m going to make sure that as far as I’m concerned and as far as the rest of the Cabinet are concerned, we are going to help her do that.”

Asked about Mr Johnson’s contribution to the Cabinet, Ms Rudd replied that he brought "enthusiasm, energy and sometimes entertainment".

The Home Secretary said Ms Davidson “has a point” with her suggestion that Mr Johnson’s intervention was poor timing. Noting how the Foreign Secretary was an “irrepressible enthusiast” for Brexit, Ms Rudd was asked if his intervention had been helpful. “Time will tell,” she replied.

Damian Green, the PM’s deputy, tried to downplay the row, describing Mr Johnson as an “entertaining writer” and that nothing in the article came as a surprise.

Asked if he was going to be sacked, the First Secretary replied: “No, he isn’t. The reason is he, like the rest of the Cabinet and the PM, is wanting to get the best deal for the British people.”

Meanwhile, Sir Vince Cable, the Liberal Democrat leader, urged Mrs May to fire Mr Johnson.

"It's a terrible situation and it puts Theresa May in an impossible position,” declared Sir Vince, noting: "I just don't understand why she hasn't fired him.”

The party leader went on: "It's like a school that's completely out of control and the head teacher is sitting in her office paralysed and impotent.

"And if you're Mr Barnier negotiating with this Government and you've got senior Cabinet ministers with entirely opposite views of what Britain's negotiating position should be, what do you do?

"It is complete and absolute loss of authority and the Prime Minister on Monday morning should fire this guy, otherwise her own credibility is reduced to zero," he added.