British Prime Minister Theresa May will ask Queen Elizabeth for permission to form a government on Friday.
She called the snap election to win a clear mandate for her plan to take Britain out of the EU's single market and customs union in order to cut immigration.
If neither party can command a majority in parliament for their Queen's Speech, it is likely a fresh election would be called.
It's a great result for anyone who wants to see more gender equality in politics - and it's happened on the 104th anniversary of the death of suffragette Emily Wilding Davison, who spent her life fighting for the right of British women to vote.
May's aides, Nick Timothy and Fiona Hill, announced on Saturday that they had quit following sustained criticism of the campaign within the party.
Conservative and Labour figures reacted cautiously to the exit poll predicting Theresa May could have lost her overall majority.
Earlier, Arlene Foster, the leader of Northern Ireland's Democratic Unionists (DUP), confirmed she would be meeting Mrs May in Downing Street on Tuesday with a view to finalising a deal to prop up a minority Tory government.
The tone of Brexit talks, tentatively scheduled to begin in just 10 days - and even May's own position - are now up in the air. The main opposition Labour Party surpassed expectations by winning 262.
Lasted: until 1931, but amid the Great Depression, MacDonald formed "National" coalition government of Conservatives, Liberals and small number of Labour MPs which won 1931 and 1935 elections.More news: Attorney general to face questions on Comey firing, Russia
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The Times of London said in an editorial that "the election appears to have been, among other things, a rejection of the vague but harshly worded prospectus for Brexit for which Mrs".
Johnson tweeted that an article in the Mail on Sunday newspaper headlined "Boris set to launch bid to be PM as May clings on" was "tripe".
The Downing St. resignations came as May worked to fill jobs in her minority government and replace ministers who lost their seats on Thursday.
The DUP was founded in the 1970s by the late firebrand preacher Ian Paisley, and in the 1980s was a key player in the "Save Ulster from Sodomy" campaign, which unsuccessfully fought against the legalization of gay sex.
"One can speculate about the reasons for this, but the simple truth is that Britain is a divided country: many are exhausted of austerity, many remain frustrated or angry about Brexit, and many younger people feel they lack the opportunities enjoyed by their parents' generation".
Ruth Davidson, the leader of the Conservatives in Scotland, told the BBC she had words with May over the DUP's record on LGBT rights.
He told BBC News: "We've had our fingers burned by coalition, I don't need to tell you that, so I find it very hard to see how Tim Farron would go back on what he has already said and indeed to persuade the membership of the Lib Dems that a coalition was a good idea from our point of view". "In particular, I regret the decision not to include in the manifesto a ceiling as well as a floor in our proposal to help meet the increasing cost of social care". "When it becomes a matter for me is when people try to redefine marriage".
In Ireland, there is growing concern that by bringing the DUP into government, London will no longer be able to perform its traditional role as an impartial broker in the Northern Ireland peace process.
The Sun newspaper said senior members of the party had vowed to get rid of Ms May, but would wait at least six months because they feared a leadership contest could propel Labour's Jeremy Corbyn into power. She told Sky News: "A coalition is not on the cards, not just because of the 2015 result but because of big policy differences". "They (the DUP) are going to support us on the big Brexit, economic and security issues facing this country", he said.