Laura Kuenssberg
BBC political editor

A resignation in itself is not a surprise - but the departure of the Brexit Secretary might be the domino that causes everything else to fall.

It’s not just that it was his job to make the policy work. It’s because he has just given unhappy Brexiteers someone to rally round, and someone who sees himself as a potential challenger to the PM.

After his departure, it becomes extremely difficult for other Brexiteers unhappy about the deal to stay on.

And in the last few minutes Esther McVey has decided to leave the government.

There is speculation about Penny Mordaunt too, although sources close to her say a departure today is far from definite.

Meanwhile, No 10 is busy trying to explain its policy this morning to opposition politicians and then to Parliament in the next hour.

But there have been three resignations from government, and it’s not even 10:00 GMT.

It’s too early to say if this morning’s storm will be a hurricane that will sweep the policy, and maybe the prime minister away.

The chair of Brexit campaign group Leave Means Leave has praised Dominic Raab for quitting his post.

John Longworth - the former director general of the British Chambers of Commerce - said he had "shown his mettle and his commitment through his resignation".

He added: "The fact that two Brexit secretaries at the cut and thrust of the negotiations have now stood down on the basis that the prime minister's deal does not deliver on the results of the referendum two years ago should send a sharp signal to Westminster MPs.

"The prime minister's proposal is the worst deal in history, in voting for it, Parliament would destroy the country's faith in our democracy and fatally undermine trust in our institutions."

BBC News Channel

Image source, Getty Images

The pound is now down 1.25% against the dollar at $1.2828 following Brexit Secretary Dominic Raab's resignation.

Sterling is down 1.34% against the euro at €1.1337

Earlier today, Shailesh Vara quit as Northern Ireland Minister.

Nomura analyst Jordan Rochester said: "Raab resigning just now changes the ballgame. [It is] Hard to be optimistic on GBP in the short term.

"But equally Theresa May has survived much worse. It’s whether we get a flood of (ministerial) resignations to follow."

Victoria Derbyshire

Labour MP Owen Smith said the resignation “told you everything you need to know” about the deal, adding: “The very person who negotiated it and who ostensibly helped present it to the cabinet resigned. It is an extraordinary state of affairs.”

He told the BBC’s Victoria Derbyshire programme: “The thing I think people need to remember from Theresa May’s speech last night is she conceded it is not a choice between no deal and this deal – it is a choice between no deal, this deal and not doing Brexit.

“The only way in which she gets out of this with any dignity is going back to the people and holding another vote in order to determine whether they want this.”

BBC Radio 5 live

David Jones, former Brexit minister, has told BBC Radio 5 Live he believes Dominic Raab has done the right thing:

"I anticipated that there would be cabinet resignations and I think Dominic Raab was in the most difficult position as Brexit secretary, so it hasn’t come as a surprise. I think he’s done the right thing.

"He’d taken the job after David Davis's resignation with his eyes open – he knew the reasons why David Davis resigned, and I think it would’ve been pretty incoherent if he’d left before the negotiations had come to their conclusion.

"He doesn't feel he can lend his name to what’s agreed… I think his reasons for going are entirely right, I think the backstop is a massive problem and, as he says, we’ll be effectively stuck in a customs union almost indefinitely.

"He [Raab] had no option but to go and I applaud him for going.”

House of Commons
Parliament

Image source, HoC

Over in Parliament, International Trade Questions have begun.

Sir Edward Leigh asks if, following the Brexit draft agreement, the Department for International Trade will now be renamed the "The Department of International Trade Promotion and engagement with the Customs Union", as the UK will now be "stuck" in the Customs Union for "years to come".

International Trade Secretary Liam Fox says the UK will leave the EU in March, and will have a "fully independent trade policy" after the transition period ends in December 2020.

Victoria Derbyshire

Image source, Getty Images

Prominent Leave campaigner and leader of the House Andrea Leadsom has told reporters she is looking forward to Theresa May's statement at 10:30 GMT.

But, she added: "I think there’s a way to go before the November council.”

BBC News Channel

Image source, Reuters

Former Tory leader Iain Duncan Smith says the resignation of Dominic Raab is "devastating".

He told the BBC News Channel: "The very man who is effectively her negotiator - for him to resign saying he doesn't think this is a good deal, I think is devastating.

"It's devastating because he's been aware of all of these things and has clearly been raising these alarm bells with the prime minister.

"But it sounds like he has been ignored, because otherwise I suspect we wouldn't be in this place."

BBC News Channel

Image source, BBC News

Shadow Brexit secretary Sir Keir Starmer says the resignation of Dominic Raab as Brexit secretary "is a very serious development".

Speaking to the BBC, he says the prime minister "hasn't got the backing of her party, she hasn't got the backing of her cabinet", and now must turn to "the majority in Parliament".

"In Parliament there's always been a strong close economic relationship, with a customs union and a single market arrangement", he says.

"There's no majority" for the positions the government has been putting forward, Sir Keir says, arguing that a change of Conservative party leader wouldn't change that.

House of Commons
Parliament

Prime Minister Theresa May will read a statement this morning to MPs at 10:30 GMT in the House of Commons, setting out the terms of her proposed agreement with the EU.

Parliamentary statements are used by government ministers to address major incidents, government policies or actions, often at short notice.

The Leader of the Opposition, Labour leader Jeremy Corbyn, will then respond to the statement, before Theresa May takes further questions from MPs.

It could last for hours as the Speaker will usually allow all MPs who want to ask a question, to do so on such an important issue.

Labour’s shadow Cabinet Office minister has claimed the government is "falling apart before our eyes."

Jon Trickett said the PM no longer had authority and could not deliver on Brexit.

He said: "The government is falling apart before our eyes as for a second time the Brexit secretary has refused to back the prime minister's Brexit plan. This so-called deal has unravelled before our eyes.

"This is the 20th minister to resign from Theresa May’s government in her two year premiership.

"Theresa May has no authority left and is clearly incapable of delivering a Brexit deal that commands even the support of her cabinet - let alone Parliament and the people of our country."

Image source, PA

The pound has slipped against most major currencies after the resignation of the Brexit secretary.

Sterling dropped 1.1% to 1.28 US dollars and was 1.2% lower at 1.13 euros.

BBC News Channel

Conservative Brexiteer-MP Anne Marie-Morris has told the BBC that Dominic Raab "did the right thing" in resigning from as Brexit secretary, calling him "a man of principle".

On the future of Theresa May as prime minister, she says "now is not the time for her as leader".