- After predictions the UK's ruling Conservatives would gain seats from the election, votes were counted, leaving the Conservatives with 318 seats - 12 seats less than the 330 they had, and 8 seats short of the number needed for a majority.
AS IT HAPPENED:
The surprise election result is sending the currency into a downward spiral.
Dan Jackson, from Travel Money New Zealand, says it's a prime time for travellers heading for Britain to trade in their dollars.
"It's gonna be volatile. Probably the best thing that you can take a stab at. That's why it's probably best to get in while it's good."
Mr Jackson says it's not the first time a shock in Britain has affected its currency, with the same thing happening during Brexit negotiations last year.
"We saw exactly the same thing happen last June as we're seeing now."
Jeremy Corbyn says Brexit negotiations have to go ahead, but is calling for a "jobs first" Brexit.
When addressing staff at Labour headquarters he declared the party "the victors", and says Labour is "ready to serve this country".
Mr Corbyn also repeated a call for Theresa May to resign.
"She was saying she was doing it to bring about strong and stable government. Well this morning, it doesn’t look like a strong government, it doesn’t look like a stable government, it doesn’t look like a government that has any programme whatsoever.”
Shadow Chancellor John McDonnell has taken aim at Theresa May, telling Sky News she's a "lame duck Prime Minister".
Mr McDonnell says the Labour Party is "ready to serve the country" and "ready to form a government".
“The way that would operate is we’d put forward our own Queen’s Speech and our own Budget as well, and then would expect other parties to vote for it.”
The pound hit a five-month low against the euro, at €1.1322, as today's election results emerged.
In Kensington, results are so close the tellers have been told to go home and rest and return later on Friday (local time), or possibly even on Saturday.
The count has been suspended without a result.
It's one of four seats left to decide, with results also pending for Cornwall North, Cornwall South East, and St Austell & Newquay.
BBC's political editor says Theresa May has "no intention of resigning".
Laura Kuenssberg added, however: "It's not clear to me whether they're trying to kill the rumours off before she truly makes her mind up."
ITV News' political editor says the Labour party wants to form a minority government.
Robert Preston says the party will challenge the Scottish National Party, Green and the Liberal Democrats to support it.
Former Tory Chancellor George Osborne believes Brexit "went in the rubbish bin tonight".
"Theresa May is probably going to be one of the shortest serving prime ministers in our history," Mr Osbourne told ITV News.
And this from Nigel Farage, former UK Independence Party leader:
Politicians are weighing in on Theresa May's leadership.
Former labour leader Ed Miliband says Ms May can't now negotiate Brexit for Britain, as she's destroyed her authority.
The Green party has won its first seat.
Co-leader Caroline Lucas retains her spot in Brighton Pavilion on the south coast of England.
An update on party seats so far:
Lib Dems 12
A hung parliament has been confirmed.
There's now no chance of a Conservative party majority, even with 23 seats still left to claim.
The result means the party has lost the slim majority they held when Theresa May called the election.
Voter turnout this year is the highest it's been since 1997, at nearly 69 percent with 27 seats still left to declare.
In New Zealand, 72 percent voted in the 2014 election - one of the lowest voter turnouts recorded for our country.
A record-high number of women have been elected for parliament this year.
There were 191 women in the last parliament, accounting for 29.4 percent of MPs.
So far this year 192 women have been elected.
Before the last parliament the record high was set in 2010, when 143 women were elected.
The UK Green Party continue to see the lighter side of the election:
Theresa May should "consider her position", following a "dreadful" election campaign which is expected to see her Conservative Party lose its parliamentary majority, an MP from her party says.
"She's in a very difficult place, she's a remarkable and a very talented woman and she doesn't shy from difficult decisions, but she now has to obviously consider her position," Anna Soubry told the BBC.
"Theresa did put her mark on this campaign, she takes responsibility as she always does, and I know she will, for the running of the campaign."
Home Secretary Amber Rudd has kept her seat by only 346 votes, a result so close it went to a recount.
Media reported Ms Rudd could have been in trouble after an exit poll showed the Conservatives falling short of the number of seats required to form a majority.
In the 2015 election she had a majority of 4,796.
Rudd, who was one of the most visible ministers in the campaign, increased her share of the vote by 2.3 per cent to 46.9 per cent, but her Labour Party opponent increased his share by 11.1 per cent to come within a whisker of winning the Hastings and Rye constituency.
An update on party seats so far:
Lib Dems 10
Jeremy Corbyn awkwardly boob slaps Emily Thornberry during a high-five gone wrong.
Speaking after his defeat, Alex Salmond says his 30-year long parliamentary career has been “the privilege of my life".
"I’m grateful for these times, for the activists in the SNP who have made the many electoral successes possible.”
He adds the public has "not seen the last of him".
Alex Salmond, former First Minister of Scotland, has lost his seat to Colin Clark.
Clark won 21,861 to Salmond’s 19,254 - a majority of 2,607.
Scottish National Party leader Nicola Sturgeon says the results of the election are disappointing for her party but were disastrous for Prime Minister Theresa May.
"Clearly it's a disappointing result, we've lost some tremendous MPs," Nicola Sturgeon says.
"This is a disaster for Theresa May, she called an election clearly very arrogantly thinking that she was going to crush the opposition, sweep everybody aside and cruise to a landside majority, her position is very, very difficult."
Sturgeon says she would think about her demands for a second Scottish independence referendum after her party lost seats to the Conservatives, Labour and Liberal Democrats, which all want to preserve the United Kingdom.
"There is clearly uncertainty around Brexit and independence which clearly will be factor in tonight's results - you know a lot of thinking for the SNP to do," she says.
Labour is currently at 197 seats and Conservative holds 191.
Jeremy Corbyn says it's time for Prime Minister Theresa May to stand down after election results indicated she had lost votes, support and the confidence of voters.
"This election was called in order for the prime minister to gain a large majority in order for her to assert her authority," he said in London, speaking after being re-elected in Islington North.
"If there is a message from tonight's results, it's this: the Prime Minister called this election because she wanted a mandate," Corbyn said.
"Well the mandate she's got is lost Conservative seats, lost votes, lost support and lost confidence."
"I would have thought that's enough to go, and make way for a government that will be truly representative of all of the people of this country."
Earlier, he said Labour's campaign in the election "has changed politics for the better".
Prime Minister Theresa May's Conservatives were forecast to win 322 seats at a national election, the BBC says, more than the 314 predicted by an initial exit poll and closer to the 326 threshold needed to form a majority.
The updated forecasts gave the Labour 261 seats.
Theresa May has held on to her Maidenhead seat for the Conservatives.
She is now speaking at the count in Maidenhead, and is thanking her returning officer and her staff. She also thanks police and those who have supported her.
"It is a huge honour being MP here.
"If the Conservative party has won the most seats and most votes, it will be incumbent on it to ensure that stability… The country needs a period of stability."
Labour has taken Glasgow North East from the Scottish National Party. Anne McLaughlin has been defeated by Labour's Paul Sweeney. It's another huge loss for the SNP with polls from the BBC, ITV and Sky suggesting SNP will win only 34 seats, down from 56 in the last general election.
Former Liberal Democrat leader Nick Clegg has lost his seat to Labour, it has been confirmed. Mr Clegg narrowly held on to Sheffield Hallam in 2015 by 40 percent to 35 percent.
Labour's Jared O'Mara is the new MP for the constituency. It's thought a surge in student voting in the university-heavy seat influenced his win.
It's the first time Labour has ever won the seat since its creation in 1885.
Labour's deputy leader Tom Watson said early election results were "very, very bad" for Conservative leader Theresa May, and his party would hold her to her statement that if she loses her majority, Labour's Jeremy Corbyn would be Prime Minister, Reuters reports.
"We still don't know the final result of this election, it is too early to say, but it looks likely to be a very, very bad result for Theresa May," Mr Watson said, after he held his seat.
Voter turnout in the UK is so far up by 3 points, but could still be below 70 percent at the end of the night, the BBC reports.
Even then, it would be the highest turnout in UK general elections since 1997.
The first government minister to lose their seat is Jane Ellison in London's Battersea, where she's been defeated by Labour.
The unexpected exit poll predicting Theresa May's Conservative Party won't get a parliamentary majority could create turmoil around upcoming Brexit talks.
A hung parliament could play in Labour's favour even if it wins less seats than the Conservatives, because it is politically closer to smaller rivals on several issues.
Jeremy Corbyn is committed to heeding the results of Britain's EU membership referendum (Brexit) a year ago, in which 52 percent voted Leave against 48 percent in favour of Remain.
But Labour has fought to water down Ms May's Brexit strategy which could make it easier to reach a compromise with either the Liberal Democrats, which has ruled out any coalition, or the pro-European SNP, which says it wants to stop another Conservative government.
Labour leader Jeremy Corbyn has issued a statement:
"I'd like to thank all our members and supporters who have worked so hard on this campaign, from door knocking to social media, and to everyone who voted for a manifesto which offers real change for our country.
"Whatever the final result, we have already changed the face of British politics."
As vote counts and seat results are announced, some on social media are blaming the Conservatives' poorer-than-expected result on Theresa May's early election choice.
"Running through fields of wheat is now officially the second worst thing Theresa May ever did," Times journalist Sam Coates said, referring to the Ms May's recent admission that the naughiest thing she ever did was run through a field of wheat.
As of 11:45am, the Conservatives have five seats, and Labour have eight.
Sky News reporter Jason Farrell is outside Labour leader Jeremy Corbyn's house, where armed police have arrived to stand guard.
In the second seat to be counted - Houghton and Sunderland South - Labour won again, but has lost votes since the last election. Overall it's seen a 3.5 percent swing from Labour to Conservative, the Guardian reports.
Labour have stocked up on Domino's pizza for the night.
Minority right-wing party UKIP leader Paul Nuttall has criticised Theresa May on Twitter.
"If the exit poll is true then Theresa May has put Brexit in jeopardy. I said at the start this election was wrong. Hubris," he wrote.
If Ms May's party doesn't get 326 seats, it will rely on UKIP in a coalition or minority government.
It would also need the Liberal Democrats, but leader Nick Clegg has ruled out that option as well.
The pound dropped heavily as the exit poll was announced, revealing the shocking prediction of a hung parliament.
In the chart below, 21:10 UTC is 9:10am NZ time.
Former British finance minister George Osborne says the exit poll forecasting Prime Minister Theresa May will lose her majority in parliament would be "completely catastrophic" for her and the Conservative Party.
"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," he told ITV.
Current Home Secretary Amber Rudd could potentially lose her seat if the exit poll proves correct, the BBC reports.
There's the chance Theresa May could be replaced by Boris Johnson.
The first result is in. The Labour Party's Chi Onwurah wins first seat of the night, with Newcastle Central, the BBC reports.
It's significant as it shows a swing from the Conservatives to Labour, the Guardian says.
The first vote results are about to come in.
Polling booths have closed in the UK and votes are now being counted.
Exit polls around the country are suggesting a very close margin between the parties could cause a hung parliament.
The British pound has dropped sharply after the exit poll result.
In the UK a party must win 326 seats to secure an absolute majority. If the leading party does not get this majority, it must form a coalition with minor parties or rule as a minority government and rely on the minor parties.
The exit poll puts the Conservatives at 314. In the last three years the Conservative Party has been a majority Government with 330 seats in Parliament.
Some predictions before voting closed said the Conservatives could get up to 400 seats.
A minority Conservative government could probably rely on the votes of about 10 unionists from Northern Ireland, but a minority Labour-led government (or the "coalition of chaos" as Theresa May called it) could rely on Plaid Cymru (3), the one Green MP and the SDLP (3 in the last parliament), the Guardian reports.
Exit polls are when pollsters approach one voter out of a given number (i.e. one out of every six/eight/ten etc.) based on the estimated national turnout agreed in advance between the polling companies and the broadcasters, the Independent says.
As many as one in five UK voters were still undecided this week after the seven-week campaign.
Most polling stations had increased security as they opened on Thursday morning, with armed police reinforcing regular officers at some locations.
Ms May smiled but did not speak to media as she and her husband Philip voted in the village of Sonning on the River Thames in her Maidenhead constituency.
Mr Corbyn grinned broadly and gave the thumbs-up to reporters and party workers as he voted in Islington, north London.
In the final hours of campaigning, both leaders returned to their core campaign messages, with Ms May's focus on Brexit and Mr Corbyn promising more money for government services.
Ms May's campaign has not gone to plan, and as the poll leads of 20 points or more she was enjoying when she called the early election in April have shrunk, talk of a landslide victory has faded and her personal standing has taken a hit.
Meanwhile, veteran left-winger Mr Corbyn, who was written off as a no-hoper by most political analysts, surprised on the upside with a policy-rich campaign that drew large, fervent crowds to his events - although sceptics say his appeal in the broader electorate is limited.
He proposes building a fairer society through policies such as raising taxes for the richest five percent, scrapping university tuition fees and investing £250 billion (NZ$448 billion) in infrastructure - plans which the Conservatives say are fiscally irresponsible.
There's just one hour left for voters to get to polling booths in the UK, and vote counting is underway.
The British tradition of #dogsatpollingstations is a popular hashtag on Twitter. Here's a selection of the best:
There's heightened security at polling booths in the UK as the country is on alert following terror attacks in Manchester and London.
Auckland University politics professor Jennifer Curtin told The AM Show Theresa May has the election in the bag.
"There's only one poll that's showing Labour ahead, and only by one point, and that poll uses a completely different method to all the others. So I'd say it's not going to be who's going to win, it's going to be how much will Theresa May win by."
Europe correspondent Tova O'Brien says it's what Ms May needs to strengthen her hand in Brexit negotiations.
"There's also a much heavier police presence, at all polling stations across the UK - this of course after those two terror attacks that suspended campaigning."
In regard to the competition between the two rival parties Conservatives and Labour, she says it hasn't been a very dramatic campaign.
Opinion polls show Labour has gained on the Conservatives in recent weeks, who held a slim lead as voting began. Voting ends at 9am (NZ time).
An Ipsos poll taken over two days this week gave the Conservatives 44 percent of the vote to Labour's 36 percent.
Conservative Prime Minister Theresa May called the snap general election seven weeks ago in a bid to strengthen her hand in Britain's divorce negotiations with the European Union. Her party is expected to increase its parliamentary majority.
Ms May has seen her once-commanding lead over the Labour Party and its veteran hard-left leader Jeremy Corbyn narrow sharply since she surprised almost everyone by calling a snap election in April.
Mr Corbyn - a former union leader known for his activism and anti-austerity policies - has been seen in the UK as having the more successful election campaign.
The election has been marred by several fatal terrorist attacks - one at Manchester Arena, and two in London.
Reuters / Newshub.