Britain's opposition Labour Party narrowly held on to a parliamentary seat in eastern England on Friday, seeing off a challenge from Nigel Farage's insurgent Brexit Party to win by less than 700 votes.

The Brexit Party, which was established in April, swept to victory in the United Kingdom's European Parliament election last month, riding a wave of anger over Prime Minister Theresa May's failure to deliver Brexit on time.

Labour candidate Lisa Forbes won with 10,484 votes, while the Brexit Party came second on 9,801 votes. May's governing Conservatives came third with 7,243 votes.

"Despite differing opinions across our city, the fact that the Brexit Party have been rejected here in Peterborough shows that the politics of division will not win," Forbes said in her victory speech.

Forbes, who backed remaining in the EU in 2016 but said she respects the result of the referendum, said May's successor should restart government talks with Labour leader Jeremy Corbyn which failed to find a way through the deadlock on Brexit.

Almost three years since Britain voted 52 percent to 48 percent to leave the European Union, lawmakers remain at loggerheads over how, when or even whether to leave the EU.

May will step down as leader of her Conservative Party on Friday, formally triggering the race for a successor who will try where she failed to deliver Brexit.

May will remain prime minister until a new leader is chosen, likely in late July, but has relinquished control over the direction of Britain's tortuous departure from the European Union.

Eleven Conservative MPs are currently vying to replace her, including former foreign minister Boris Johnson, but some are expected to drop out before Monday's deadline for nominations.

Despite failing to win the seat, the Brexit Party's lead over the Conservatives will increase the pressure on those running to replace May to pursue a cleaner break with the bloc.

The winner will have only a few months to decide whether to try to salvage May's plan, delay Brexit again, or sever ties with Britain's closest trading partner with no agreement at all.

May took office after the 2016 referendum vote to leave the EU and has spent the past three years working on the plan, delaying Brexit twice to try to get it through.