A London gambler has bet £200,000 on Donald Trump becoming the next president of the United States.

The man, who has not been named, stands to win £500,000 on top of the original sum, if the Republican candidate defeats Democrat Hillary Clinton in Tuesday’s election.

The enormous gamble comes after bookies announced the 2016 US presidential election had smashed betting records, with more wagers expected to be placed on the outcome than on the Euro 2016 final, the EU referendum, or the Derby.

Bookies slashed their odds on Mr Trump winning on Friday after a customer from Nottingham placed £37,000 on a Republican victory.

Since then, gamblers across Britain have placed several six-figure bets on both candidates winning the race to White House.

The £200,000 bet was made on online betting site Spreadex.

Connor Campbell, a financial analyst at Spreadex, said: “It's official, the US election is now our single biggest betting event ever and we are seeing some huge bets being placed, including one customer who has staked £200,000 on a Trump victory.”

William Hill said its largest bets included a London-based telephone client who staked £150,000 on Hillary Clinton becoming America's first female president, and a Durham woman who put £183,200 on Ms Clinton in a two-part wager.

John Mappin, who owns a castle in Cornwall, could take home £100,000 after putting 30 bets on Mr Trump walking into the White House, the Press Association reported.

William Hill spokesman Graham Sharpe said: ”The US election campaign has smashed all previous election betting records, with the biggest betting turnover for any political event, with £20m riding on the outcome industry-wide.

“William Hill alone are about to exceed a £4m turnover for the first time on any political event, and with the result still too close to call we anticipate a political bets bonanza in the closing hours of the election campaign.”

US election 2016: the race for the White House in pictures Show all 12 1 /12 US election 2016: the race for the White House in pictures US election 2016: the race for the White House in pictures Republican U.S. presidential nominee Donald Trump shakes hands with Democratic U.S. presidential nominee Hillary Clinton at the conclusion of their first presidential debate at Hofstra University in Hempstead, New York Reuters US election 2016: the race for the White House in pictures President Barack Obama embraces Democratic nominee Hillary Clinton on stage at the party's convention in Philadelphia US election 2016: the race for the White House in pictures Donald Trump's wife Melania delivered a speech at the GOP convention in Cleveland that was later found to have been cribbed in part from Michelle Obama's 2008 convention address AP US election 2016: the race for the White House in pictures Hillary Clinton talks to reporters aboard her new campaign plane on Labour Day, 5 September, her first 'press conference' since 2015 (Getty Images) US election 2016: the race for the White House in pictures Donald Trump held a joint press conference with Mexican leader Enrique Pena Nieto in Mexico City in August, hours before reiterating his harsh immigration plans at a campaign rally in Arizona Reuters US election 2016: the race for the White House in pictures Bernie Sanders officially endorsed Hillary Clinton, saying his progressive vision for ‘a transformed America’ would be ’best served by the defeat of Donald Trump’ Reuters US election 2016: the race for the White House in pictures Khizr and Gazala Khan appeared at the DNC to slam Trump for his stance on Muslim immigration, citing the case of their son Humayun Khan, who was killed in combat while serving as a Captain in the US Army in Iraq US election 2016: the race for the White House in pictures Libertarian candidate Gary Johnson is doing better in polls than any third party candidate since Ross Perot, 20 years ago Nicholas Kamm/AFP/Getty US election 2016: the race for the White House in pictures Green Party candidate Jill Stein (centre) marches with supporters in Colorado AP US election 2016: the race for the White House in pictures Hillary Clinton and Virginia Senator Tim Kaine at a rally in Kaine's home state in July, days before Ms Clinton tapped him to be her running mate Getty US election 2016: the race for the White House in pictures Trump on the campaign trail with his vice presidential pick, Indiana governor Mike Pence AP US election 2016: the race for the White House in pictures Former Ukip leader Nigel Farage appears at a Trump rally in Mississippi in August, where he told the crowd that he 'wouldn't vote for Hillary Clinton if you paid me'.

Meanwhile, a Ladbrokes customer who staked £100,000 on Ms Clinton taking the top spot is set to take away £125,000 if the prediction is correct.

Ladbrokes estimates 35 bets a minute will be placed as Britons stay up into the early hours of Wednesday morning to hear the result.