'The honour of my life' - Theresa May in tears as she announces she will stand down as Conservative Party leader
- Will end her turbulent reign as Conservative leader on June 7
- Boris Johnson is the early favourite to replace her
- Varadkar: Brexit in a new phase that may be 'very dangerous for Ireland'
The UK will have a new prime minister by the end of July as a tearful Theresa May was finally forced to set out the timetable for her exit from Number 10 Downing Street.
The British Prime Minister will end her turbulent reign as Conservative leader on June 7, paving the way for a potentially brutal contest to replace her.
The next prime minister is expected to be in Number 10 by the time the House of Commons rises for its summer recess and leadership contenders are already ramping up their efforts ahead of the official start of the contest.
British Foreign Secretary Jeremy Hunt indicated he would stand, while bookmakers' favourite Boris Johnson sought to secure the Brexiteer vote by stressing he would be prepared to back a no-deal departure to ensure the UK leaves the EU on October 31.
In an emotional statement in Downing Street, with husband Philip and her closest aides watching on, Mrs May said it was in the "best interests of the country" for a new prime minister to lead efforts to deliver Brexit.
Her voice cracked as she said: "I will shortly leave the job that it has been the honour of my life to hold - the second female prime minister but certainly not the last.
"I do so with no ill-will, but with enormous and enduring gratitude to have had the opportunity to serve the country I love."
With Mr Johnson the current favourite to replace her, and former Brexit secretary Dominic Raab his nearest contender, Mrs May warned against a hardline approach, saying a consensus was necessary.
"Such a consensus can only be reached if those on all sides of the debate are willing to compromise," she said.
Her resignation puts Brexit in a new phase that may be "very dangerous for Ireland", Taoiseach Leo Varadkar has said.
Mr Varadkar said Mrs May's departure could lead to the election of a "Eurosceptic" prime minister.
He said her successor may scrap the Brexit withdrawal agreement.
"We may see the election of a Eurosceptic prime minister who wants to repudiate the withdrawal agreement and go for no-deal, or we may even see a new British government that wants a closer relationship with the EU and goes for a second referendum," said Mr Varadkar.
But Mr Varadkar added the government will "hold its nerve".
"We are going to build and strengthen our alliances across the European Union and we will make sure that we see Ireland through this," he added.
Mr Varadkar said Mrs May was "principled, honourable, and deeply passionate about doing her best for her country".
"Politicians throughout the EU have admired her tenacity, her courage, and her determination during what has been a difficult and challenging time," he said.
Tanaiste Simon Coveney warned the UK would not get a better Brexit deal than that negotiated with Theresa May
"This idea that a new prime minister will be a tougher negotiator and will put it up to the EU and get a much better deal for Britain? That's not how the EU works," Mr Coveney told Newstalk.
He said a further Article 50 extension, delaying Brexit, was "possible and may be likely".
Mrs May will remain in office until the leadership process is concluded.
The timetable for the contest will see nominations close in the week of June 10, with MPs involved in a series of votes to whittle what is set to be a crowded field down to a final two contenders.
The Conservative hierarchy promised that members and non-members would get the chance to question the would-be prime ministers during the election process.
Labour leader Jeremy Corbyn said Mrs May's replacement should call an immediate general election.
Mrs May's statement came after a bitter backlash against her last effort to get a Brexit deal through Parliament.
A Cabinet mutiny and the prospect of the backbench 1922 Committee allowing another confidence motion eventually forced the Prime Minister's hand.
She insisted she had "done my best" to deliver Brexit and take the UK out of the European Union.
But almost three years after the UK voted to break away from Brussels, Mrs May said: "It is, and will always remain, a matter of deep regret to me that I have not been able to deliver Brexit.
"It will be for my successor to seek a way forward that honours the result of the referendum."
Mr Hunt, MP for South West Surrey, heavily hinted he will join the race to replace Mrs May, telling his local newspaper the Farnham Herald: "I'll make the announcement on my own candidacy at the appropriate time."
An ally of the Foreign Secretary told the Press Association "we will be saying more in the coming days about that".
Meanwhile, Mr Johnson was at a conference in Interlaken, Switzerland, and said he would seek to renegotiate the Brexit deal if he became prime minister.
But he stressed that "you need to be prepared to walk away" without a deal if necessary in order to ensure the UK does actually leave the EU.
Mr Raab, in a sign his campaign is gathering momentum, received a boost as Tory MP Helen Grant quit as a vice chairwoman of the party to back his leadership bid.
She said the former Brexit secretary "has an inspiring vision for a fairer Britain and I think he is undoubtedly the best person to unite the Conservative Party and our country".
And Sir Graham Brady quit as the leader of the 1922 Committee - a position which gave him a significant role in the Prime Minister's departure - in order to consider a leadership bid.
He told the Press Association: "I have been approached by a number of colleagues across the party both inside and outside Parliament asking me to put myself forward as a candidate.
"Therefore I have taken the decision to stand down from the position of chairman of the 1922 Committee in order to ensure a fair and transparent election process."
Within minutes of the Prime Minister's statement, Cabinet colleagues - including some who have ambitions to replace her - paid tribute to Mrs May.
Environment Secretary Michael Gove - who stood in the 2016 leadership race and may consider another bid - said Mrs May "deserves our respect and gratitude".
Home Secretary Sajid Javid, who had a "frank" discussion with Mrs May about her deal on Thursday, said "nobody could have worked harder or had a greater sense of public duty".
Labour leader Mr Corbyn said: "The last thing the country needs is weeks of more Conservative infighting followed by yet another unelected prime minister.
"Whoever becomes the new Conservative leader must let the people decide our country's future, through an immediate general election."
Former prime minister David Cameron offered his sympathy to Mrs May, saying "I know how painful it is to accept that your time is up and a new leader is required".
With additional reporting by PA