Boris Johnson is on course to secure a Conservative majority in the House of Commons, according to the exit poll.
The poll forecasts the Tories will win 368 MPs, to Labour's 191, giving them a Commons majority of 86.
The SNP would have 55 seats and the Liberal Democrats 13, adding one seat to the 12 they won in 2017.
The Brexit Party would win no seats, Plaid Cymru three and the Greens one.
If borne out by the actual results, the prime minister will return to Number 10 on Friday with a considerable majority which will, in theory, enable him to drive through his Brexit deal and take the UK out of the European Union next month.
It would represent the largest majority for a Conservative leader since Margaret Thatcher in the 1980s.
The result will be seen as a triumph for his tightly-controlled election campaign, which was largely gaffe-free until the final week.
It will, however, be a significant set-back for the Labour leader Jeremy Corbyn, who will have twice led his party to defeat at the polls.
Mr Johnson entered the election without a majority - having just 298 Tory MPs - after some quit the party and he withdrew the whip from others when they rebelled over Brexit.
MORE: General Election 2019: Norfolk and Waveney results and reaction
Labour, who had 243 MPs when Parliament was dissolved last month, is forecast to have lost 52 seats.
Polling expert Michael Thrasher, from the School of Sociology, Politics & Law at the University of Plymouth, said: "For Labour it really is an appalling election result and possibly its worst performance in any general election since the second world war.
"So Jeremy Corbyn, I'm afraid, will go down as one of the worst leaders in Labour's history."
Norwich South Labour candidate Clive Lewis said he was not going to speculate on what that sort of loss might mean for his party and its leader.
But, of the exit poll, he said: "It looks pretty decisive and that's something Jeremy will have to reflect on."
Trevor Wainwright, Labour leader at Great Yarmouth Borough Council, said the exit poll was "really very disappointing" and the future of the party, including its leadership will "have to be looked at".
North West Norfolk Labour candidate Jo Rust said the exit poll was "incredibly disappointing" because it was "contrary to what we have experienced" during the campaign.
Former Labour spin doctor Alastair Campbell tweeted: "Dreadful result if true but in some ways all too predictable. The country decided some time ago Jeremy Corbyn not going to be PM and Boris Johnson made a promise on Brexit which enough people were prepared to believe."
Norwich North Labour candidate Karen Davis said, if the exit poll proves to be correct it would be "devastating for the NHS, people who need mental health services in Norfolk and anyone suffering from cuts made by the Conservatives."
Jess Barnard, Labour candidate for Broadland said of the exit poll prediction: "As much as it is disheartening, it won't be the end of the movement. We just need to get back up and keep fighting.
"Jeremy has been the target of a concerted media campaign against him.
"The manifesto we've created and put forward is absolutely what people need and I stand by that.
"But we've got more work to do in bringing people along with us and communicating that to the public."
And Great Yarmouth independent candidate Adrian Myers, said if the polls were accurate there will "be no Brexit". He said: "It means we're not going to get out.
Bill Borrett, chairman of Mid Norfolk Conservative Association, said the exit poll was "certainly more encouraging than that of 2017", but confessed he was "extremely nervous because it has felt like quite a close campaign."
He added: "I know from previous experience, until they've counted the votes, you can't take anything for granted."
And Tom Herman, deputy chairman of the North Norfolk Conservatives, said: "It's very encouraging, but of course, let's wait until the votes are in and counted until we get carried away."
Former Conservative Waveney leader Mark Bee said: "It is good to see it pointing towards a very clear and decisive result coming through. We have noticed locally a very solid Conservative response."
And Ian Sherwood, election agent for Conservative candidates, Liz Truss in Norfolk South West and James Wild in Norfolk North West, said: "I'm always cautious, but the exit poll tallies with our polling and what the canvassing had predicted locally.
"I would not say I was surprised by the national picture but it is pleasing to have it confirmed. Obviously there has only been the initial results come in, but they are looking very promising.
"Our canvassing had given us some local figures that we thought were on the high side but we were expecting to increase our share of the vote in both seats and it looks like that is going to happen. So we are really pleased."
Richard Bacon, looking to hold South Norfolk for the Conservatives, said people on the doorstep hold told him they did not like Jeremy Corbyn.
He said: "He's been a really important figure in this election and Boris Johnson has attained a winning campaign."
But Steffan Aquarone, Liberal Democrat candidate in Mid Norfolk, said: "It really is surprising that the people of Great Britain have decided to vote for a man who hides in a fridge to avoid answering questions."
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