BORIS Johnson has sensationally resigned as Foreign Secretary, throwing Theresa May's Government into further turmoil after the departure of David Davis as Brexit Secretary.

The resignations of the two Cabinet "big beasts" come just days after Mrs May secured senior ministers' agreement at Chequers for a Brexit plan about which both men had expressed reservations.

Mr Davis was first to go, announcing his exit just before midnight on Sunday.

Boris Johnson's last tweet as Foreign Secretary

But there was growing speculation about Mr Johnson's plans on Monday after he failed to attend a meeting of the Government's Cobra emergencies committee as well as a summit of Western Balkan nations being held in London.

At 3pm on Monday, a statement was issued by Downing Street to say: "This afternoon, the Prime Minister accepted the resignation of Boris Johnson as Foreign Secretary. His replacement will be announced shortly. The Prime Minister thanks Boris for his work."

Staunch Brexiteer Dominic Raab was named as Mr Davis's replacement as Secretary of State for Leaving the EU.

Labour's deputy leader Tom Watson said: "Theresa May's Government is in meltdown. This is complete and utter chaos.

"The country is at a standstill with a divided and shambolic Government. The Prime Minister can't deliver Brexit and has zero authority left."

European Council President Donald Tusk has said the "mess caused by Brexit is the biggest problem in the history of EU-UK relations", according to reports.

The Foreign Secretary's six-strong motorcade has left the official residence, but the official car remains outside.

Mr Johnson had yet to appear, 20 minutes after news of his resignation was announced.

Liberal Democrats leader Sir Vince Cable said: "He might have taken time to pluck up the courage to join his hard Brexiteer colleagues, but Boris Johnson's resignation completely destroys the Conservative position.

"Johnson had already described the proposals as 'a turd', and now they will surely be flushed away."

Mrs May said she wanted to recognise the work of the former Brexit Secretary on steering through some of the "most important legislation for generations".

The Prime Minister said she also wanted to "recognise the passion" that the outgoing Foreign Secretary had shown in promoting a "global Britain to the world".

Brexit Minister Lord Callanan was answering questions at the despatch box in the House of Lords when he was informed of Mr Johnson's resignation by opposition frontbencher Lord Stevenson of Balmacara.

He said: "I'm obviously sorry to hear that the Foreign Secretary has resigned.

"If what the Lord says is correct he has been a towering figure in the Government."

A short time earlier, Tory peer Lord Cormack said throughout the party there were "many, many people" who would be delighted Lord Callanan, a staunch Brexiteer, was staying in his post "supporting the Prime Minister in trying to support a sensible settlement".

Lord Callanan sparked laughter when he said: "I thought there was going to be a 'but' there."

He added: "I was somewhat surprised to wake up this morning to find Lord Adonis had apparently announced my resignation on Twitter, which was perhaps wishful thinking on his part."

Some Labour MPs shouted "resign" while others waved "bye" as Mrs May took to the despatch box.

Labour leader Jeremy Corbyn said there was a "crisis in Government" after the resignation of the two Cabinet ministers.

He told the Commons: "It is clear this Government is not capable of securing a deal to protect the economy, jobs and living standards.

"It is clear this Government cannot secure a good deal for Britain."

Mr Corbyn told the Commons: "We are two years on from the referendum - two years of soundbites, indecision and Cabinet infighting, culminating in a series of wasted opportunities with more and more people losing faith that this Government is capable of delivering a good Brexit deal.

"And that is just within her own Cabinet."

Mr Corbyn added: "There are now only a few months left until these negotiations are supposed to conclude. We have a crisis in Government, two secretaries of state have resigned and still we are no clearer on what the future relationship with our nearest neighbours and biggest partners will look like.

"Workers and businesses deserve better than this. It is clear... this Government is not capable of securing a deal to protect the economy, jobs and living standards. This Government cannot secure a good deal for Britain."

Mr Corbyn asked: "How can anyone have faith in the Prime Minister getting a good deal with 27 European Union governments when she can't even broker a deal within her own Cabinet?"

He also criticised the new Brexit Secretary Dominic Raab, telling MPs: "This new Secretary of State is on record as wanting to 'tear up people's rights'."

Mr Davis said it was a "pity" that the Foreign Secretary had quit.

Asked about his reaction by Iain Dale on LBC, he replied: "Regret, really. I had resigned because this was central.

"This was central to my job and if we continue with this policy and I was still there, I'd have to present it in the House of Commons. I'd have to present it in Europe. I'd have to be the champion of the policy which I didn't believe in, so that doesn't work.

"Somebody else can do a better job than me under those circumstances. I don't think it's central to the Foreign Secretary. It's a pity, but there we are."

Mr Davis denied coordinating his resignation with Mr Johnson.

"No, no. I told a number of ministers last night just before, well just after actually, now I think about it, I decided what to do, but that was just to keep them informed."

What do the resignations of Boris Johnson and David Davis mean for Theresa May's Government and the Brexit deal?

What do the resignations of Boris Johnson and David Davis mean for Theresa May's Government and the Brexit deal?

Add your contribution now By uploading a contribution, for use online and in print, you accept our contributor terms. You will either own or have permission to use anything you provide.