THERESA May has sent a defiant message to her opponents that she is staying to deliver a Brexit deal.

After a dramatic day of resignations and letters of no confidence being sent to the Tory 1922 Committee, the Prime Minister came out fighting.

Mrs May lost two of her Cabinet and another junior minister less than a day after the Cabinet backed the draft Brexit agreement in Downing Street.

With the pro Brexit wing of the Tories poised to challenge her position Mrs May said she believed “with every fibre of her being” that what she was doing was right.

She added: “Am I going to see it through? Yes”.

The Prime Minister took a swipe at those who had resigned saying she was acting in the best interests of the country.

She said: “My approach throughout has been to put the national interest first. Not a partisan interest. And certainly not my own political interest.”

However, she added: “I do not judge harshly those of my colleagues who seek to do the same but who reach a different conclusion. They must do what they believe to be right, just as I do.

“I am sorry that they have chosen to leave the government and I thank them for their service.

“But I believe with every fibre of my being that the course I have set out is the right one for our country and all our people.”

Mrs May said not to back the deal would lead to “deep and grave uncertainty”.

She said: “I understand fully that there are some who are unhappy with those compromises.

“But this deal delivers what people voted for and it is in the national interest.

“And we can only secure it if we unite behind the agreement reached in Cabinet yesterday.

“If we do not move forward with that agreement, nobody can know for sure the consequences that will follow.”

She spoke following two more high profile resignations plunged the Tories into chaos.

First, Brexit Secretary, Dominic Rabb, who negotiated the draft agreement, resigned, then Work and Pension Secretary, Esther McVey, quit her post.

Both said the deal put the integrity of the United Kingdom at risk.

Earlier Tory MP and chair of the European Research Group of pro-Brexit backbenchers Jacob Rees-Mogg struck the first blow in what could lead to a challenge to Mrs May’s leadership.

The Euro-sceptic said he expected that the threshold of 48 letters would be reached but denied he was staging a coup.

Mr Rees-Mogg, in his letter to the 1922 Committee chairman, sir Graham Brady, said the deal has: “Turned out to be worse than anticipated and fails to meet the promises given to the nation by the Prime Minister.”

The old Etonian MP for North East Somerset said he was not putting himself forward as a contended but named several who could be.

He listed Dominic Raab, Esther McVey, Boris Johnson, David Davis and Penny Mordaunt as possible leadership successors.

Even if she survives a no confidence vote from her own party, the Prime Minister still faces a battle to get the draft agreement approved in a vote in the House of Commons next month. Opposition parties have said they will oppose it

Both pro Brexit and remainers in the Tory party have said they will not support it, Labour and the SNP will also vote against it.

And with the Northern Irish MPs in the Democratic Unionist Party, which the Prime Minister relies on for a majority, speaking out against it, it is unlikely to command enough support.

Labour’s Brexit spokesman Sir Keir Starmer said it was a “second rate document”.

In the house of Commons, Labour leader Jeremy Corbyn, said the Prime Minister should “withdraw he half-baked deal”.

He said it was clear it did not have the backing of the cabinet nor the country as a whole.

The Liberal Democrats are actively campaigning for a people’s vote on the deal which could see the UK remain in the EU will vote against it.

As well as Mr Raab and Ms McVey quitting, Northern Ireland Minister Shailesh Vara and junior Brexit minister.,Suella Braverman also left their posts.

They join Jo Johnson who quit as Transport Minister last week and David Davis as Brexit Secretary, Boris Johnson as foreign Secretary in July along with junior ministers Steve Baker at Brexit and Guto Bebb at Defence.