Labour leader Jeremy Corbyn speaks after the results was given at Sobell Leisure Centre for the Islington North constituency for the 2019 General Election. (PA Images)

A quarter of Leave-backing Labour voters defected to the Conservatives on Thursday, a new poll has found.

Jeremy Corbyn has blamed Brexit for his defeat and while that has been disputed, Labour’s position on the issue saw it lose 25% of Leavers who backed the party in 2017 to the Tories, according to a survey by Conservative peer Lord Ashcroft.

Boris Johnson won Thursday’s election despite only taking a slightly higher percentage of the vote than Theresa May did in 2017.

Meanwhile, Labour’s vote share collapsed from 40% in the previous election to 32%.

Speaking on election night, Mr Corbyn praised Labour’s manifesto and said: “All of those policies were extremely popular during the election campaign and remain policies that have huge popular support all across this country.

Lord Ashcroft's findings. More

“However Brexit has so polarised and divided debate in this country it has overridden so much of a normal political debate and I recognise that has contributed to the results that the Labour party has received this evening all across this country.”

The Tories made leaving the EU a central plank of their election campaign and used the slogan “Get Brexit Done” throughout.

They ended up taking seats that have returned Labour MPs for decades but voted Leave in 2016, including Bolsover, Workington and Tony Blair’s former seat, Sedgefield.

View photos Prime Minister Boris Johnson hammers in a Conservative placard into a front garden whilst canvassing in Benfleet, Essex, during the final day of General Election campaigning. (PA Images) More

Meanwhile, 84% of Leavers who voted Labour in 2017 stayed loyal this time.

Just 66% of Tory Remainers from the last election returned to the fold, with 21% defecting to the Liberal Democrats, but 92% of Leavers who voted Conservative in 2017 stayed blue this time.

However, the notion of whether Brexit was the only factor in Labour’s defeat has been heavily disputed, with politicians and voters saying Mr Corbyn played a key role himself.

Lord Ashcroft’s poll showed how Brexit ranked ahead of the NHS as the main concern for people who voted Tory.

Of the 13,000 people polled on election day, the most important issue for voters was the NHS, with 55% of people putting it in their top three issues when read various topics from a list, with just 36% including getting Brexit done.

View photos The slogan was used in a stunt during the final stint of the campaign. (PA Images) More

But between Conservative voters only, 72% put getting Brexit done in their top three priorities. The next two issues to most frequently appear in the top three were the NHS and the economy.

Labour and SNP voters prioritised the NHS and then stopping Brexit, with poverty and inequality coming third for both parties’ supporters.

Lib Dem voters put stopping Brexit as the top priority, followed by the NHS and climate change.