EU referendum
Final YouGov poll gives Remain a four-point lead, but Leave strikes back - follow our live updates
2.10am: The Leave side has breached the million-vote mark in Britain's referendum on EU membership, in what looks like being a very close race.
Leave has established a lead of nearly 140,000 votes, with 39 of the 382 local areas declared. However, results are yet to come in from London and other large cities, which are expected to back Remain.
ITV News reports that Remain is on course to take between 55 and 60 per cent of the vote in Birmingham, the most populous local authority area. And many London boroughs are projected to go for remain by a margin of 70 to 30 or more.
But Leave has made the early running, with a better-than-expected showing in the north of England, particularly Newcastle and Sunderland.
"If Leave are over-performing in the north-east," says the BBC's Jeremy Vine, "Remain are going to have to over-perform somewhere else to make up."
The Daily Telegraph's Tim Stanley has some calming words for the pro-Europeans.
"We're all very excited about the early results from the northeast because they've shown that working-class, industrial areas are coming out for Leave big time," he says. "But hold fire. We might see that balanced out by voting in London. Moreover, I think Leave should be mildly anxious about the Swindon result. It was closer than they expected. Swindon is swing Labour/Tory. More representative, perhaps, of the rest of the nation."
1.35am: The race is tight, but it appears to have swung very slightly back towards Remain. The University of East Anglia's politics blog, which is projecting the outcome based on declared results, suggest the In campaign will end up with 50.2 per cent of the vote. An hour ago, after Newcastle and Sunderland declared, it had predicted a 50.2 per cent win for Leave. "Best not to read too much in the probability when that predicted vote share is so close to 50:50," it says.
Three more Scottish areas have voted to Remain: Dundee, West Dunbartonshire and Western Isles. But with 14 results in (and 368 yet to declare), the Leave side is 14,537 votes ahead.
Now might be a good time to note that the legislation that set up the EU referendum made no provision for a dead heat.
1.15am: London turnout may be two or three per cent lower than might have been expected says polling expert John Curtice, which is more bad news for the Remain campaign – London is one of the most pro-European parts of the country, and was expected to contribute a significant proportion of the Remain vote.
But Jon Stone, The Independent's political correspondent, says "the Remain campaign is still smiley despite the latest news."
The Swindon result may have given them a little more to smile about. Although Leave won by ten points, it was broadly in line with the projected result. "We are seeing it stabilise it a little bit," says the BBC's Jeremy Vine. "Sunderland and Newcastle may be outliers."
Nevertheless, after a 66 to 34 per cent win in Broxbourne, and a 61 to 39 per cent win in Kettering, the Brexiters are winning. With 11 areas declared, they have a lead of 6,818 votes
"I've learned it's not wise to predict these things, from long and bitter experience," Ed Miliband tells Sky News.
12.50am: Having begun the evening on a wave of confidence, the Remain campaign appears to be in retreat as early results suggest a strong showing for the Leave campaign.
With only a tiny proportion of results declared, Leave is ahead by 3,207 – but what has put a spring in the step of the Brexiters is their unexpected success in two northern cities: Newcastle and Sunderland.
In Newcastle, Leave narrowly lost, but by a margin of just 0.6 per cent. It had been expected to vote clearly for Remain. And in Sunderland, where Leave was expected to win, the margin was 22 points – much greater than expected.
The currency markets have reacted accordingly. Having reached a 2016 high of $1.50 as the polls closed, the pound dipped to $1.44 as Leave notched up better than expected results in Newcastle and Sunderland – but it has since crept back up to $1.46.
The Daily Telegraph quotes Joe Rundle of ETX Capital: "Markets are very nervy at the moment as the polls – and the markets – could be wrong. The Sunderland result has definitely altered the tone of the evening and markets are getting very choppy."
However, trading volumes are low, which means small changes can result in large swings.
12.25am: Sunderland has delivered the first win of the evening for Leave, and it's a strong one - with a 61 to 39 per cent margin in favour of Brexit. That's about twice the gap that had been forecast.
"This is a huge result for the Leave campaign and will certainly unsettle those thinking Remain have got it in the bag," says the Daily Telegraph.
The pound has fallen from the nine-month high of $1.50 it reached as polls closed, slipping to $1.44.
Clackmannanshire and Orkney have both voted to Remain, but the overall tally - which is what will count - shows a lead for Leave of just over 3,000.
12.10am: Voters in Newcastle have voted to stay in the European Union, but by only the slimmest of margins, raising the hopes of the Leave campaign.
Demographic models had suggested that the Remain campaign would need 60 per cent of the vote in the city to be on course for victory, but it won by only 50.7 per cent to 49.3.
There were positive signs for Leave in Sunderland too, where the BBC's Laura Kuenssberg says the Brexit vote may be as high as 62 per cent. "That would be quite something," she tweeted.
Polling expert John Curtice said that if David Cameron had been feeling relaxed about the result, he may now have put the champagne back in the fridge.
Earlier, the first result of the evening had come from Gibraltar, which voted overwhelmingly for Britain to stay in the EU. On a turnout of 84 per cent, 19,322 people voted for Remain and just 823 for Leave.
11.15pm: The last opinion poll of the campaing suggests that Britain will vote to Remain in the European Union, by a relatively narrow margin. The YouGov survey of 5,000 people - which is not an exit poll, and is no more likely to be accurate than other campaign polls - found that 52 per cent of voters backed Remain, compared with 48 for Leave.
But The Guardian quotes one source in the Remain campaign who says a 55 to 45 per cent win is "on the cards"
A few moments ago, Nigel Farage appeared to concede defeat, telling Sky News that "turnout looks to be exceptionally high and [it] looks like Remain will edge it."
The pound has risen to $1.50 on the news - it's highest level since September last year.
"Investors know no more than the rest of us about who has won," says the BBC's economics editor Kamal Ahmed, "but the markets seem to think that Remain has had a strong day at the polls."
Chris Grayling, the Conservative supporter of Leave, said it was "far too early" to say which side has won. And Arron Banks, the co-founder of Leave.EU, said a private poll of 10,000 people conducted by his organisation had found precisely the reverse of the YouGov survey: a 52 to 48 advantage for Leave.
In public, most Remain supporters are being more cautious. "I am reasonably confident that hopefully remain gets the result," Labour's Chuka Umunna said on Sky News. "But it could go the other way."
Paddy Ashdown, the former Lib Dem leader who was forced to eat a marzipan hat after wrongly dismissing the general election exit polls last year, said, "The truth is that nobody knows."
Reports are trickling in from around the country that turnout has been high. In Gibraltar, likely to be solidly Remain, some 83.65 per cent of voters cast their ballots. "Some unusually high turnouts are being reported around Oxfordshire" too, says The Guardian's Richard Adams.
9.50pm: The polls are about to close in Britain's referendum on EU membership, with counting due to get underway at 10pm.
Polls published this morning suggest a narrow advantage for Remain, but the lead has been fluctuating poll by poll.
With no exit poll due – the broadcasters decided against commissioning one, fearing that it would prove inaccurate – a
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