A former singer in the Eurovision-winning band Bucks Fizz will stand for the Brexit Party at the next general election.

Jay Aston Colquhounis – who will run in the Labour-held seat of Kensington – was among the latest wave of candidates announced by party leader Nigel Farage at a rally in Westminster.

Ms Colquhounis joined Bucks Fizz when the band was formed in 1981 – later that year they won Eurovision with their cheery hit Making Your Mind Up – before quitting in 1985. The 58-year-old said she wanted to “fight to uphold democracy for the sake of the people”.

"As an MP, I will work to rebuild trust and help the Brexit Party make the necessary reforms to unite the country after we break free of the European Union," Ms Colquhounis said.

Mr Farage said 635 approved candidates had now “passed their assessments” and the party would be prepared to stand in every single seat against the Conservatives – unless Boris Johnson delivered a no-deal Brexit.

The Brexit Party leader dangled the promise of a “non-aggression pact” with the Tories if the prime minister pursued what he called a “clean-break Brexit”.

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Mr Farage said: “If Boris Johnson is prepared to do the right thing for the independence of this country, then we would put country before party and do the right thing.”

Welcomed to the stage by the sound of tolling bells, the former Ukip leader told the crowd of chosen candidates they had not wasted their time by getting involved in his new party.

There was – he predicted – “a greater than 50 per cent chance that we will face a general election in the autumn.”

Nigel Farage speaks during a rally for Brexit Party candidates in Westminster (Reuters)

Despite recent poll evidence to the contrary, Mr Farage also claimed: “A clean-break Brexit on the 31st October is now by far the most popular option in this country.”

The latest BMG poll for The Independent shows only 34 per cent of voters actually want the prime minister to carry out a no-deal Brexit, while the latest Survation poll shows only 19 per cent favour leaving the EU without a deal.

The process of getting those 635 Brexit Party candidates finalised has not been plain sailing for Mr Farage and his team.

Earlier this month the party listed Mark Nash as a candidate for the Moray constituency, before The National newspaper revealed he had written Islamophobic blogs under the pseudonym “Moraymint” – describing Islam as a “cancer” that had to be “crushed out of existence”.

Mr Farage’s party then claimed Nash had failed vetting and was added to a press release “in error”.

Other candidates include former lads’ mag editor Martin Daubney and Dominic Frisby, a stand-up comedian.