Media playback is unsupported on your device Media caption Theresa May asked about no-confidence vote: "Am I going to see this through? Yes."

Theresa May has dismissed speculation she could be ousted as prime minister over her Brexit agreement, saying: "I am going to see this through."

Despite a series of ministers resigning and talk of a no-confidence vote, she vowed to get the deal signed off in Brussels and to put it to MPs.

"The course I have set out is the right one for our country," she said.

The BBC understands Michael Gove has rejected Mrs May's offer to become the new Brexit secretary.

BBC political editor Laura Kuenssberg said Environment Secretary Mr Gove had said he might accept - if he could try to make changes to the negotiated deal.

Sources said Mrs May made it clear that was not possible. He is now considering his position and contemplating resignation.

Other sources have told the BBC a wider group of ministers were discussing whether to try to force the PM to seek changes to the deal.

Earlier, Brexit Secretary Dominic Raab and Work and Pensions Secretary Esther McVey both quit in protest at the withdrawal agreement, along with two junior ministers.

And leading backbench Brexiteer Jacob Rees-Mogg submitted a letter of no confidence in Mrs May to Sir Graham Brady, chairman of the Tories' backbench 1922 Committee.

A vote will be triggered if 48 Tory MPs write letters to Sir Graham - it is understood 48 letters have not yet been received.

Mrs May spent nearly three hours fielding largely critical questions from MPs before holding a press conference in Downing Street to further answer her critics.

Media playback is unsupported on your device Media caption "Negotiations give away on all key points": Jacob Rees-Mogg on the PM's draft Brexit deal

She acknowledged the agreement negotiated with the EU had entailed "difficult and sometimes uncomfortable decisions".

"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," she said.

"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.

"It will be to take a path of deep and grave uncertainty when the British people just want us to get on with it. They are looking to the Conservative Party to deliver."

Asked if she would carry on as prime minister if she won a no-confidence vote by a single vote, Mrs May said: "Leadership is about taking the right decisions, not the easy ones."

She said her job was to "bring back a deal that delivers on the vote of the British people".

She added: "I believe this is a deal which does deliver that, which is in the national interest and am I going to see this through? Yes."

Media playback is unsupported on your device Media caption How the Conservative Party handles a leadership challenge

The prime minister, a cricket fan, was asked if she would "resign as captain", but told journalists Geoffrey Boycott, famed for his batting marathons, was one of her sporting heroes: "And what do you know about Geoffrey Boycott? Geoffrey Boycott stuck to it and he got the runs in the end."

Amid suggestions she was struggling to fill the two cabinet posts vacated by Dominic Raab and Esther McVey earlier on Thursday, she joked: "I have had, actually, rather a busy day."

The BBC understands that Environment Secretary Michael Gove had been offered the job as Brexit Secretary but had asked for assurances that he could pursue a different kind of deal.

Mrs May said Mr Gove was doing "an excellent job at Defra" adding: "I haven't appointed a new Dexeu [Department for Exiting the European Union] secretary yet and I will be making appointments to the government in due course."

Analysis

By BBC Political Editor Laura Kuenssberg

The government, for today at least, is at the mercy of events not in control.

Theresa May's vow to stay does not make her deep, deep problems disappear.

With her party in revolt, her colleagues departing - some determined to usher her out of office - we can't, and don't know yet, if Brexit can happen as planned, perhaps, if at all.

This could be a gale that's weathered in a few days, or a serious storm that sweeps the government away.

Read Laura's blog

Meanwhile German Chancellor Angela Merkel said there was no appetite for further talks on possible amendments to the current agreement: "We have a document on the table that Britain and the EU 27 have agreed to, so for me there is no question at the moment whether we negotiate further."

Despite a warning from Tory backbencher Mark Francois earlier that it would be "mathematically impossible to get this deal through the House of Commons", Mrs May said she believed, ultimately, her MPs would back it.

"I'm committed, as prime minister, to bringing the best deal back to the UK. I think MPs across my party who look at that deal will recognise the importance of delivering on the vote of the British people and recognise the importance of doing that in a way that does protect people's jobs, protect security and protect the unity of our United Kingdom."

Media playback is unsupported on your device Media caption BBC's Laura Kuenssberg asks the PM if she "in office, but not really in power?"

But Liberal Democrat leader Sir Vince Cable suggested the prime minister was "in denial": "The facts haven't changed. There is no majority in Parliament for her deal, and she has rightly conceded that "No Brexit" is the real alternative to it."

He said it strengthened the case for another referendum "to break the deadlock and get the country out of this mess".

Earlier Labour Leader Jeremy Corbyn described the deal negotiated with the EU as "half-baked" and urged her to withdraw it.

He told MPs: "This is not the deal the country was promised and Parliament cannot - and I believe will not - accept a false choice between this bad deal and no deal."

But Northern Ireland Secretary Karen Bradley defended the prime minister, saying "there is no better person to do this job".

She said collective responsibility meant that ministers who could not support the deal were required to resign, but added: "The majority of the cabinet is behind it. The remaining members of the cabinet are absolutely behind this deal and what we need to do now is get behind the prime minister and get that deal sorted in the November (European) Council."