London (dpa) - British voters were deciding Thursday whether or not their country should leave the European Union, in a referendum that could send shockwaves around the 28-country block and the world.
Voting at 41,000 polling stations was taking place as torrential rains caused flooding in London and the south of the country, causing travel headaches and soaking people as they went to cast their ballots.
The weather could have an effect on the so-called Brexit referendum, whose results were expected to be close.
"Actually I do think we are in with a very strong chance, I do genuinely," said Nigel Farage, head of the UK Independence Party and an outspoken leader of the exit campaign.
"But it's all about turnout and those soft remainers staying at home," he told British news agency Press Association outside his home in Kent.
A final poll published by The Evening Standard newspaper that was conducted Wednesday showed 52 per cent wanting to stay in the EU, against 48 per cent wishing to depart. However, 12 per cent said they might change their mind at the last minute.
A last-minute survey conducted for the Daily Mail newspaper and broadcaster ITV put the Remain vote on 48 per cent, Leave on 42 per cent and 11 per cent undecided.
Bookmakers have also given Remain a higher chance of victory than Leave.
"The bookies usually get it right," British Labour chief Jeremy Corbyn said as he arrived to cast his ballot in London.
Although political rivals, opposition chief Corbyn and conservative Prime Minister David Cameron had both campaigned for Britain to stay in the EU.
Much of the debate focussed on the economy and EU migration, particularly in the last few weeks before the referendum.
The Remain camp argues that an exit from the EU's common market would hurt the British economy and would cost jobs, a view that is shared by other EU countries, as well as by leading economists around the world.
In addition, financial markets could be thrown into turmoil if Britons vote the EU's second largest economy after Germany out of the bloc.
It would be the first time that a country decided to leave the EU.
However, market sentiment was still positive Thursday as the British pound reached its highest level of 1.48 dollars, and European stock indeces were up.
"The markets are clearly anticipating a victory for the opponents of Brexit," said Jochen Stanzl, a Frankfurt-based analyst at CMC Markets.
In an attempt to calm markets in the case of a Brexit, dpa has learned that the finance ministers of the G7 group of leading industrialized nations are preparing a joint statement.
The ministers are working in coordination with their countries' central banks and will release the statement from Tokyo shortly after the referendum's result is known.
Cameron, under pressure from those in his own Conservative party and a rising euroscepticism among British voters, had promised in 2013 to hold a referendum on EU membership.
He called the referendum in February after negotiating a package of reforms with the bloc that he said gave Britain a "special status."
Polls are open until 10 pm (2100 GMT), with first local results expected in the early hours of Friday and the final result around 7 am. About 46.5 million people are registered to vote.