Departure of Theresa May is now inevitable - The Yorkshire Post saysA tearful Prime Minister said she had "done my best" to get her Withdrawal Agreement through Parliament and take the UK out of the European Union but acknowledged she had failed.
"It is and will always remain a matter of deep regret to me that I have not been able to deliver Brexit," she said in Downing Street.
Watched by husband Philip and her closest aides, an emotional Mrs May said it was in the "best interests of the country for a new prime minister to lead that effort".
Announcing her departure from a job she loved, Mrs May said: "I am today announcing that I will resign as leader of the Conservative and Unionist Party on Friday 7th June so that a successor can be chosen."
Nigel Farage will be Prime Minister unless Brexit is delivered - Bill CarmichaelConcluding her resignation statement, which is in full below, Mrs May broke down as she said it had been "the honour of my life" to serve "the country that I love".
Earlier, in a sign that the leadership race to replace Mrs May is already under way, Helen Grant quit as Conservative vice chair for communities to "actively and openly" support Dominic Raab.
She quit her Tory party role to avoid any "perception of a conflict" between Mr Raab's campaign and Conservative HQ".
Ms Grant 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".
Business leaders have already started to react.
Carolyn Fairbairn, Confederation of British Industry Director-General, said: “The Prime Minister could not have worked harder to deliver a Brexit deal that protects the economy.
"She leaves office with the respect of business.
“But her resignation must be now be a catalyst for change. There can be no plan for Britain without a plan for Brexit. Winner takes all politics is not working. Jobs and livelihoods are at stake.
“Business and the country need honesty. Nation must be put ahead of party, prosperity ahead of politics. Compromise and consensus must refind their voice in Parliament.
“We call on politicians from all parties, on all those ambitious to lead, to take this chance for a fresh start.”
Mrs May's statement in full:
"Ever since I first stepped through the door behind me as Prime Minister, I was driven to make the United Kingdom a country that works not just for a privileged few but for everyone, and to honour the result of the EU referendum.
"Back in 2016, we gave the people the British people a choice.
"Against all predictions, the British people voted to leave the European Union.
"I feel as certain today as I did three years ago that in a democracy, if you give people a choice you have a duty to implement what they decide.
"I have done my best to do that.
"I negotiated the terms of our exit and a new relationship with our closest neighbours that protects jobs, our security and our union.
"I have done everything I can to convince MPs to back that deal.
"Sadly, I have not been able to do so. I tried three times. I believe it was right to persevere, even where the odds against success seemed high.
"But it is now clear to me that it is in the best interests of the country for a new prime minister to lead that effort.
"So I am today announcing that I will resign as the leader of the Conservative and Unionist Party on Friday 7 June so that a successor can be chosen.
"I have agreed with the party chairman and with the chairman of the 1922 committee that the process for electing a new leader should begin in the following week.
"I have kept Her Majesty the Queen fully informed of my intentions and I will continue to serve as her Prime Minister until the process has concluded.
"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.
"To succeed, he or she will have to find consensus in Parliament where I have not.
"Such a consensus can only be reached if those on all sides of the debate are willing to compromise.
"For many years the great humanitarian, Sir Nicholas Winton, who saved the lives of hundreds of children by arranging their evacuation from Nazi-occupied Czecheslovakia through the Kindertransport, was my constituent in Maidenhead.
"At another time of political controversy a few years before his death, he took me to one side at a local event and gave me a piece of advice.
"He said: 'Never forget that compromise is not a dirty word. Life depends on compromise.' "He was right.
"As we strive to find the compromises we need in our politics, whether to deliver Brexit or to restore devolved government in Northern Ireland, we must remember what brought us here.
"Because the referendum was not just a call to leave the EU, but for profound change in our country, a call to make the United Kingdom a country that truly works for everyone.
"I'm proud of the progress we have made over the last three years.
"We have completed the work that David Cameron and George Osborne started. The deficit is almost eliminated.
"Our national debt is falling and we are bringing an end to austerity.
"My focus has been on ensuring that the good jobs of the future will be created in communities across the whole country, not just in London and the South East, through our modern industrial strategy.
"We have helped more people than ever enjoy the security of a job. We are building more homes and helping first-time buyers onto the housing ladder, so young people can enjoy the opportunities their parents did.
"And we are protecting the environment, eliminating plastic waste, tackling climate change and improving air quality.
"This is what a decent, moderate and patriotic Conservative government on the common ground of British politics can achieve, even as we tackle the biggest peacetime challenge any government has faced.
"I know that the Conservative Party can renew itself in the years ahead, that we can deliver Brexit and serve the British people with policies inspired by our values.
"Security, freedom and opportunity. Those values have guided me throughout my career. But the unique privilege of this office is to use this platform to give a voice to the voiceless. To fight the burning injustices that still scar our society.
"That is why I put proper funding for mental health at the heart of our NHS long term plan.
"It's why I'm ending the postcode lottery for victims of domestic abuse.
"It is why the race disparity audit and gender pay reporting are shining a light on inequality so it has nowhere to hide.
"And it is why I set up the independent inquiry into the tragedy at Grenfell Tower, to search for the truth so nothing like it can ever happen again, and so the people who lost their lives that night are never forgotten.
"Because this country is a union. Not just a family of four nations, but a union of people, all of us. Whatever our background, the colour of our skin, or who we love, we stand together, and together we have a great future.
"Our politics may be under strain but there is so much that is good about this country, so much to be proud of, so much to be optimistic about.
"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."