Theresa May will seek to stay on as Prime Minister and Tory leader despite failing to win a majority after her decision to hold a snap election backfired spectacularly.
As the June 8 poll ended in a hung parliament, with no party holding an absolute majority in the House of Commons, Mrs May pledged the Tories would offer "stability" as the largest party with the most votes.
But Conservative former minister Anna Soubry said she should "consider her position" and take personal responsibility for a "dreadful" campaign and a "deeply flawed" manifesto after choosing to go to the country three years early in the hope of extending her majority.
Labour leader Jeremy Corbyn called on the Prime Minister to resign, saying she should "go and make way for a government that is truly representative of this country".
But Tory sources indicated she would continue in Number 10.
"Certainly that's what's expected," a source said.
But former chancellor George Osborne, sacked from the Cabinet by Mrs May and now editor of the Evening Standard, told ITV: "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."
With 646 out of 650 constituencies declared, the Tories had 315 seats, Labour 261, the SNP 35 and the Liberal Democrats 12.
The Democratic Unionist Party, which increased its representation at Westminster from eight to 10, signalled it was ready to discuss working with the Tories on issues such as Brexit and keeping the UK together.
With the party in a position to hold the balance of power at Westminster, senior MP Sir Jeffrey Donaldson said the DUP would be "serious players" in the hung parliament, telling the BBC: "This is perfect territory for the DUP because obviously if the Conservatives are just short of an overall majority it puts us in a very strong negotiating position and certainly that is one we would take up with relish."
The influential ConservativeHome website, edited by former MP Paul Goodman, said the "consensus view" among Tory backbenchers and ministers is that the Prime Minister's authority has "received a blow from which it is unlikely to recover".
Mr Goodman said they believed Mrs May's two closest advisers, joint chiefs of staff Nick Timothy and Fiona Hill "must go" and there could be major changes to the Brexit process, single market membership "may now be on the table", the website said.
He added: "All this, remember, is on the assumption that May somehow gains a working majority, or is Prime Minister in a hung Parliament.
"In the latter circumstance, a second election in the autumn will be likely.
"With the threat of a second election hanging over their heads, Conservative backbenchers would be unlikely to mount a leadership challenge, but May's days as leader would be numbered."
Sinn Fein head Gerry Adams said he could not see Prime Minister Theresa May surviving in her post and that there is "no danger whatsoever of us taking our seats in the Westminster parliament."
He credited Labour leader Jeremy Corbyn with fighting a good campaign despite "media bias".
"I don't know how Theresa May can survive this, that's a matter for her party, of course," he said.
The pound plummeted as the shock figures set the scene for political turmoil at Westminster, disruption to upcoming Brexit negotiations and the possibility of a second election later in the year.
The night was marked by a collapse in Ukip support and a rash of high-profile losses for the SNP, as British politics returned to a two-party system on the greatest scale since the 1970s.
The Tories lost seven frontbenchers, with ministers Jane Ellison, Simon Kirby, Gavin Barwell, James Wharton, Nicola Blackwood and Rob Wilson going down to defeat, along with Cabinet Office minister Ben Gummer, the author of the widely criticised Tory manifesto.
Ukip leader Paul Nuttall faced humiliation in Boston & Skegness, where he came in a distant third, and the eurosceptic party lost its only Westminster seat in Clacton.
As Ukip voters switched to Labour and the Tories across the country, Mr Nuttall said Mrs May had put the Brexit process in "jeopardy" just 10 days before talks were due to begin in Brussels.
High-profile casualties of a night of shock defeats included Liberal Democrat former leader and ex-deputy prime minister Nick Clegg in Sheffield Hallam, SNP former first minister Alex Salmond in Banff & Buchan and the SNP's leader in Westminster Angus Robertson in Moray.
Home Secretary Amber Rudd and Education Secretary Justine Greening hung onto their seats by the skin of their teeth with much reduced majorities.
