Taking Britain back into the EU single market would win Andy Burnham the next general election and help him achieve a legacy to rival Tony Blair’s, a former Tory minister turned Labour adviser has claimed.

Nick Boles, who served as a minister in David Cameron’s government before quitting the Conservatives in 2019 over the party’s Brexit stance, has urged the new prime minister to seize the opportunity created by “pretty scary” world events since 2016 to strike a deal with European Union leaders that would protect the continent and offer the UK a much-needed economic boost.

Mr Boles is calling for the creation of a “European Confederation”, which he says would provide some of the benefits of European integration such as single market access and youth mobility, but without having to accept free movement or being forced to join the Eurozone.

Under his proposal, which has reportedly been put to the prime minister, the UK would be invited to join the confederation in return for a commitment to spend 3.5 per cent of GDP on defence and to extend the protection of its nuclear umbrella across the continent.

He believes the move to access the single market again would also deal a “devastating” blow to the Tories and Nigel Farage’s Reform, securing victory in the next general election and writing Mr Burnham into the history books.

Polling has repeatedly shown Britons favour closer ties with the European Union, with research carried out by YouGov in June to mark 10 years since the EU referendum revealing that 59 per cent of voters support a closer UK-Europe relationship, compared with just 20 per cent who do not.

When it comes to the single market, half of Britons support rejoining compared with 26 per cent who do not.

Mr Boles, who helped to prepare Labour for office before it entered government, told The Independent: “If (Mr Burnham) sorts out social care and takes us into the single market and (a new) European Confederation, that is a more substantial legacy than anyone in the last few years. It would certainly rival Blair's.”

He said a new post-Brexit deal could provide a “devastating” dividing line with other parties that would win the Labour leader the next general election, by putting the party “in a commanding position” on an “abundantly popular side” of the argument.

It would allow him to say “vote Labour to get back into the European single market…or vote Tory or Reform to stay out in impecunious isolation,” he said.

“It's a pretty devastating divide. Particularly with public opinion where it currently seems to be with regard to the success or otherwise of Brexit.”

Former Labour leader Neil Kinnock is among those who have argued that Mr Boles’ plan is a “practical approach”.

Mr Boles urged Mr Burnham, whose optimism he likened to that of the very popular former US President Ronald Reagan, to grasp the nettle.

As a new PM, he was not held to Sir Keir Starmer's ‘reset’ of relations with Europe, which faced criticism for its lack of ambition, he said.

Of Mr Burnham he said: “He refuses to be sort of bowed by... how terrible everything is, how difficult it all is, how everybody before has failed.

“You sense that he's a bit of a gambler….he likes to roll the dice,” he added.

“There's a moment in Europe, whether we take advantage of it or not - they're all talking about how they're going to deal with this changed world.”

Mr Boles said “feelers” had been put out from within the Burnham government about his essay, published earlier this month by the think tank Demos. “People are interested. People have asked to have conversations," he said.

He said the new proposal could show the UK was “humbler” and that “it's no longer ‘oh those selfish British, you know, trying to have their cake and eat it’” while also offering a solution which would be of benefit to both sides.

Mr Boles also said the political circumstances had changed drastically since the 2016 referendum.

He said it was “highly unlikely” the UK would have voted to leave the EU if the world had been as dangerous then as it is now.

“I think it is one of those sad accidents of history that the pressure to have the referendum... came to a head just at the time when it was most likely to win, and indeed, perhaps the only time when it was ever likely to win,” he said.

A government spokesperson said: "We are building an ambitious, close relationship with the EU that will strengthen our economy and create more opportunities for working people and communities across Britain."

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