Earlier May stood in Downing Street and declared her determination to carry on for a full five-year term after getting permission from the Queen to form a government, even though she spectacularly lost her Commons majority overnight.
Incredibly she failed to mention that she had humiliatingly lost seats to Labour after calling the election three years early in a bid to capitalise on sky-high poll ratings.
Around two hours later she appeared on TV again and apologised to defeated Tory MPs after she was accused "lacking humility".
May acknowledged that she had called an election three years early hoping for a "large" majority, adding: "That was not the result that we secured".
She said: "As I reflect on the result, I will reflect on what we need to do in the future to take the party forward.
"I am sorry for those candidates and hard-working party workers who weren't successful but also particularly sorry for those colleagues who were MPs or ministers who had contributed so much to our country and who lost their seats and didn't deserve to lose their seats."
May today refused to say if her election disaster has killed off Britain's chances of a good deal to leave the EU - with former Chancellor George Osborne saying: "Hard Brexit went in the rubbish bin last night".
Senior MPs such as Sarah Wollaston, Anna Soubry and Nicky Morgan have openly called for Mrs May to step aside - with the latter suggesting she should go within 'weeks or months' because her credibility is shot.
One senior Tory MP told ITV News: "We all f***ing hate her. But there is nothing we can do. She has totally f***ed us".
Earlier, following an audience with the Queen, May said she would seek to lead a minority government supported by the Democratic Unionists (DUP).
"What the country needs more than ever is certainty, and having secured the largest number of votes and the greatest number of seats in the General Election, it is clear that only the Conservative and Unionist Party has the legitimacy and ability to provide that certainty by commanding a majority in the House of Commons,' she said in a statement on the steps of No 10.
"As we do, we will continue to work with our friends and allies in the Democratic Unionist Party in particular.
"Our two parties have enjoyed a strong relationship over many years, and this gives me the confidence to believe that we will be able to work together in the interests of the whole United Kingdom."
Her frontbench team including Chancellor Philip Hammond and Defence Secretary Michael Fallon have been silent since the election disaster and a jubilant Jeremy Corbyn demanded she make way for him to become PM.
Boris Johnson publicly refused to back her as PM and some MPs said the Foreign Secretary, who has long harboured leadership ambitions, was out "on manoeuvre".
Brexit Secretary David Davis is the only one to have made a clear declaration that she should stay, insisting he would fight 'tooth and nail' to keep her in post.
But her closest aides Nick Timothy and Fiona Hill could be sacked as MPs lined up to blame them for several of her campaign catastrophes including the dementia tax that played so badly with voters. One source said Timothy was not with Mrs May in Downing Street today.
South Cambridgeshire MP Heidi Allen said: "I don't think Theresa May can stay any longer than six months. If the leader picks people who advises them so badly - it's not the leader that we need."
Tory MP Philip Davies said the party made "a pig's ear" of the campaign and backbencher Nigel Evans said: "We didn't shoot ourselves in the foot, we shot ourselves in the head".
Former Chancellor George Osborne called the manifesto the worst in history and said that the poor result meant that "Hard Brexit went in the rubbish bin".
A surge in seats won by the Scottish Tories from the SNP saved her skin - but using her growing influence leader Ruth Davidson said May must listen to non-Tory voters and pursue "an open Brexit not a closed one".
Former minister Rob Wilson, who was booted out in the election, took a swipe at the PM's closest aides Fiona Hill and Nick Timothy saying the government could not be run by such a "small group".
Even the DUP, whom May must now rely on to keep her in Downing Street, said it would be 'difficult' for her to cling on. Meanwhile, it is not yet clear what price the party will extract in return for propping her up as premier.
The only thing saving May from utter disaster overnight was the Tory performance in Scotland. The party's leader north of the border, Ruth Davidson, inspired a 12-seat surge that ousted the SNP's former First Minister Alex Salmond in Gordon and Westminster leader Angus Robertson in Moray.
With one seat left to declare, the Conservatives are on track to wind up with 318 MPs, Labour 261, the SNP 35 and the Lib Dems 14. For an absolutely majority a party needs 326 seats out of the 650 in the Commons - although taking into account the impartial Speaker and the fact that Sinn Fein does not take up its seven seats, 320 is enough.
Support from the DUP, which is in line with the Tories on most issues, pushes her over the threshold. Ironically, it means that her effective majority is 17 - exactly the same figure as when she triggered the election six weeks ago.
Looking uncomfortable as she delivered a statement on the steps of No10 this afternoon, May defied the reality of her wafer-thin majority by insisting she is still determined to serve five years in office.
And she vowed to lead a government that would crackdown on terrorism and "keep our country safe" in the wake of the atrocities in London and Manchester - despite painful questions about the number of chances missed by the police and MI5 to stop the murderers.
"What the country needs more than ever is certainty and having secured the largest number of votes and the greatest number of seats in the general election, it is clear only the Conservative and Unionist Party has the legitimacy and ability to provide that certainty by commanding a majority in the House of Commons," she said.
"As we do, we will continue to work with our friends and allies in the DUP in particular. Our two parties have enjoyed a strong relationship over many years.
"This gives me the confidence to believe we will be able to work together in the interests of the whole UK.
"This will allow us to come together as a country and challenge our energies toward a successful Brexit deal that works for everyone in this country, securing a new partnership with the EU that guarantees our continued prosperity.
"That's what people voted for last year. That's what we will deliver. Now let's get to work."
Speaking at a press conference this afternoon, DUP leader Arlene Foster said she spoke with May this morning to "explore how it may be possible to bring stability to our nation".
In yet another rollercoaster ride of political drama overnight:
• London was a horrorshow for the Conservatives, with Education Secretary Justine Greening only just hanging on in Putney and Treasury minister Jane Ellison losing in Battersea after a 10 per cent swing to Labour. But Zac Goldsmith squeaked back in Richmond Park by just 45 votes.
• In total eight ministers have been ousted, including Cabinet Office minister Ben Gummer from Ipswich, Gavin Barwell from Croydon Central, Nicola Blackwood from Oxford West, Rob Wilson from Reading East, Simon Kirby from Brighton Kemptown, Edward Timpson in Crewe & Nantwich, and James Wharton from Stockton South.
• The SNP endured a dreadful night with their numbers at Westminster forecast to plummet from 54 to 34. The party's former First Minister Alex Salmond lost Gordon, and Westminster leader Angus Robertson was defeated in Moray.
• Former Ukip leader Nigel Farage said he would have "absolutely no choice" but to return to active politics if the result meant Brexit was under threat. "We may well be looking down the barrel of a second referendum," he said.
• The Liberal Democrats are set to get 12 seats, up from nine, despite widespread expectations that they would be put to the sword after a dire campaign. Former Lib Dem leader Nick Clegg lost Sheffield Hallam to Labour - but former business secretary Vince Cable fared better as he made a comeback in Twickenham and Ed Davey is returning in Kingston and Surbiton.
• The pound tumbled dramatically against the US dollar and the euro as markets had priced in a solid Tory victory.
Corbyn today repeated his demand for May's resignation, adding he and party were "ready to serve" and were preparing to form a minority government. He insisted: "That's what we fought the election for."
He said: "We are offering to put forward the programme on which we fought the electon. We are there as the Labour Party... everyone can see the huge increase in our support."
Corbyn said Parliament should meet on schedule and MPs would then have a vote - but refused to concede May had the right to present her Queen's Speech as the leading party and the incumbent, as constitutional convention demands.
The Labour leader could force a vote on his own plans by tabling an amendment to May's Queen's Speech.
In a victory speech after winning Islington North for the ninth time, Corbyn said: "This election was called by the Prime Minister to gain a large majority in order to assert her authority.
"The election campaign has gone on for the last six weeks, I have travelled the whole country and you know what: politics has changed.
"Politics is not going back into the box where it was before. What has happened is people have said they have had quite enough of austerity politics, they have had quite enough of the underfunding of the health service, underfunding our schools and education service."
He added: "I am very proud of the results coming in around the country tonight, of people voting for hope, hope for the future and turning their backs on austerity.
"If there is a message from tonight's result it is this: the Prime Minister called the election, she wanted a mandate.
"The mandate she has got is lost Conservative seats, lost votes, lost support and lost confidence.
"I would have thought that was enough to go and make way for a government that will be truly representative of the people of this country."
But speaking at her own count in Maidenhead, a clearly shaken May said: "As we look ahead and wait to see what the final results will be, I know - as I say - the country needs a period of stability and whatever the results are the Conservative Party will ensure we fulfil our duty in ensuring that stability so that we can all, as one country, go forward together."
DUP leader Arlene Foster made clear that her party was ready to prop up May in power, although it is expected to be an informal arrangement rather than a coalition.
However, despite signalling support for the Tories she predicted it would be "difficult" for the Prime Minister to continue in her role.
"I certainly think that there will be contact made over the weekend but I think it is too soon to talk about what we're going to do," she said.
The DUP and Conservatives have been in close touch throughout May's year in power, and contacts are believed to have continued as election results came in this morning.
The Northern Irish party is thought to have been cautious about committing itself to an arrangement because of uncertainty about the future of the Tory leadership.
Asked if she thought May would be able to stay in her job, the DUP leader told the BBC: "I don't know", adding: "I think it will be difficult for her to survive."
East Belfast MP Gavin Robinson made clear the DUP would be demanding a quid pro quo for shoring up the Tory government. "I think that puts us in a fantastic position to deliver for Northern Ireland," he added.
Meanwhile, there was no sign of the big beasts in May's cabinet as she came to terms with an election result that took both main parties by surprise. Even as the polls closed last night, senior Labour sources were still telling MailOnline they were "not optimistic" and expected to lose at least 30 seats. In fact they gained nearly as many.
In contrast Tory MPs and officials were notably upbeat about their chances, even after the exit poll was published indicating they would take a hit.
As the scale of the debacle emerged last night, Johnson was asked if he believed May should carry on as Prime Minister.
But the ambitious Foreign Secretary would only say "it's early days".
He also stayed silent when a reporter suggested that the Tory leader was "fatally wounded" - and then appeared not to hear when another journalist asked him: "Does your party need a new leader? Is it you?"
Cabinet Office minister Mr Wilson told the Guardian the Tory manifesto was like an "exocet straight through the heart of our main supporters, older people".
"The party cannot have a situation whereby things are done within such a small group of people because there were too many huge mistakes - the manifesto was a huge mistake in the way it was presented. There always needs to be proper testing of ideas before they are launched," he said.
Despite Tory hopes they would be the biggest winners from a massive Ukip collapse, the exit poll at 10pm last night indicated Labour had hoovered up a big chunk of the vote. It said the Conservatives were on track to lose 16 seats, leaving them on 314 and well short of a majority - while Labour was up from 232 to 266.
However, things quickly looked even more grim for May, with Education Secretary Justine Greening barely clinging on in Putney and Treasury minister Jane Ellison losing Battersea amid a London meltdown.
Cabinet Office minister Ben Gummer was defeated in Ipswich, and there has also been a miserable showing in Wales, while Home Secretary Amber Rudd barely survived by 300 votes after a recount in her Hastings seat. Canterbury - which has been Tory for a century - also went to Corbyn's party.
With almost all declarations in, the Tories are on track to end up with 319 seats to Labour's 267 - just about enough for a workable majority, but many are expecting the final tally to be lower.
There are fears that a hung parliament could throw Britain into chaos barely a week before negotiations with the EU are due to get under way.
Former Ukip leader Nigel Farage said he was ready to return to politics, warning that he feared a second referendum on Brexit.
The exit poll was greeted with disbelief on social media, with Gary Lineker branding it the "biggest own goal" in history. Piers Morgan said the PM was "toast".
Osborne said the numbers were "catastrophic" and cast doubt on May's future.
The Evening Standard editor, who was brutally sacked from the Cabinet by May when she took office last July, lambasted the PM for her "terrible manifesto" and "wooden campaign".
But he added that Corbyn might have been the Conservatives' saving grace as another Labour leader could have won.
"Theresa May is probably going to be one of the shortest serving prime ministers in our history," he told ITV.
Osborne also raised the prospect that the Brexit process could now be totally different due to the results. "Hard Brexit went in the rubbish bin tonight," he said.
His point was underlined by former Cabinet Secretary Lord O'Donnell, who said he believed the EU would simply ignore Mrs May because she was not likely to last long.
"The prime minister has to stay as prime minister for now," he told the BBC.
"I think those negotiations on Brexit will be non- existent. It takes two sides to negotiate. The EU will say 'who are we negotiating with? Is this a prime minister who is going to be around for very much time. What's their position?'"
Soubry made no effort to conceal her anger at May when asked whether she should resign.
"That's a matter for her. It's bad. I think she in a very difficult place. She's a remarkable woman and a very talented woman but she now has to consider her position," she said.
She added: "Theresa did put her mark on this campaign and she takes responsibility, she always does and I know she will, for the running of the campaign as well.
"It was a tightly knit group and it was her group who ran this campaign"
Katie Perrior, May's former director of communications at 10 Downing Street, said it would be "incredibly difficult" for her former boss to stay as Conservative leader.
She told Sky News: "It depends whether or not the Conservative Party says 'Look, we're 10 days away from the start of the Brexit negotiations, what we need right now is a stable leader to rally around but we will look at this in a month or two and come back to it'.
'But that is whether or not they're willing to do that.
"There are a lot of bruised people out there this morning ... they're bruised because they may have had lower majorities or indeed they've got friends who have lost their seats."
Perrior said it was "damaging" for May not to take part in the televised debates, adding: "I think the communications for the campaign have been pretty awful."
But Brexit Secretary David Davis said he would "fight tooth and nail" to keep May in post, and dismissed suggestions he might be a contender to replace her.
"The simple truth is we have a Prime Minister, she is a very good leader, I'm a big supporter of hers," Davis said.
"I'll fight tooth and nail to keep her in place."
In his victory speech as he was re-elected MP for West Bromwich East, deputy Labour leader Tom Watson said: "Theresa May's authority has been undermined by this election.
'She is a damaged Prime Minister whose reputation may never recover."
Labour's John McDonnell said the result would 'change the nature of politics' in the UK.
"I tell you why - if you listen to what people are saying, Theresa May promised on seven different occasions that she wouldn't go for a snap general election," he told the BBC.
"And she went for it on the basis that she wanted to secure a mandate that she already had. People just saw through that.
"They saw this as an election which was for party advantage rather than the interests of the country. And it looks as though they've rejected her as a result."
Thornberry went on the attack, saying: "Just think only seven weeks ago the hubris of the Prime Minister who was 20 points ahead, who wanted to have a blank cheque, she wanted to do whatever she wanted with the country with Brexit, with the economy, with our National Health Service and we said no and we meant it.
"And we put forward a popular manifesto with a leader of the party who has withstood the most extraordinary personal attacks, and has actually shown if anybody was strong and stable it was him.
"And this is a great result, if it's true."
Thornberry said May should "consider her position" as she will have "manifestly failed" if the exit poll turns out to be correct.
On what Labour would do, she added: "We will see what happens next but if the Labour Party is called on to provide the next government, we will do so and do it in a unified way under a popular manifesto... with a leader who is strong."
Osborne told ITV he doubted that any party would be able to form a stable government.
"If the poll is anything like accurate this is completely catastrophic for the Conservatives and for Theresa May," he said.
"It's difficult to see, if these numbers are right, how they would put together the coalition to remain in office.
"But equally it's quite difficult to see how Labour could put together a coalition.
'It's on a real knife-edge."
He added: "Clearly if she's got a worse result than two years ago and is almost unable to form a government then she I doubt will survive in the long term as Conservative party leader."
Former shadow chancellor Ed Balls, appearing alongside Osborne on ITV tonight, predicted "another general election soon".
Ed Miliband, who stood down as Labour leader following election defeat in 2015, says: "We know Theresa May can't now negotiate Brexit for Britain because she told us losing a majority would destroy her authority, and it has."
