According to a report in The Times, UK Prime Minister Boris Johnson has been warned of a landslide defeat for Republicans next month, with Democrats on track for a “triple whammy” of seizing the Presidency, the House of Representatives and the Senate.

British ministers have been told to forge links with Mr Biden and his team, after private polling and modelling shown to 10 Downing Street last month put the chance of Democratic victory at more than 70 per cent, with one model this weekend increasing to 85 per cent.

Despite an official decision not to take sides, Mr Johnson reportedly spoke to the US President last week to wish him well for the election – but privately the British PM has all but given up on Mr Trump.

“They’re writing off Trump in No 10 now,” one senior Conservative Party member told The Times.

The newspaper reports that key British officials have been cosying up to Democrats, with UK foreign secretary Dominic Raab recently meeting with House Speaker Nancy Pelosi and other powerful Congressional figures on a visit to the US.

The British ambassador in Washington, Karen Pierce, meanwhile, has been wooing Biden campaign foreign policy advisers Tony Blinken and Jake Sullivan, who are tipped to be secretary of state and national security adviser, according to The Times.

UK officials are reportedly fearful of the impact of a Biden presidency on Brexit, believing the Democrat is more likely to side with the European Union.

Last month, Mr Biden weighed in on the issue and its possible impact on Northern Ireland.

“We can’t allow the Good Friday Agreement that brought peace to Northern Ireland to become a casualty of Brexit,” he tweeted.

A spokesman for Mr Johnson at the time suggested Mr Biden did not understand the issue.

“We continue to remain absolutely committed to no hard border and no border infrastructure between the Republic and Northern Ireland,” he told The Sun.

Asked if Mr Biden was wrong, he replied, “We will continue to work with our US partners to ensure our position is understood but the whole point of this – as the Prime Minister has set out – is to make sure the Belfast/Good Friday Agreement is upheld.”

BBC economics editor Faisal Islam explained that US politicians had always “maintained a keen interest in anything that might impact on the Good Friday Agreement, as the US was one of the guarantors of peace in Northern Ireland”.

“The US House of Representatives turning majority Democrat in 2018 was the trigger for concern among members of the British cabinet,” Islam wrote.

“Key figures in the Congressional Irish lobby … were appointed to important positions overseeing US trade deals. Since then, Irish diplomats in the US have cultivated the cross-party Irish lobby in Congress, and persuaded them to see the Brexit ‘backstop’ provisions as essential for the protection of peace in Ireland.”

A number of British MPs and officials over the weekend raised concerns that hopes of a US-UK trade deal would go out the window if Mr Biden wins.

“Recent pronouncements by Biden make clear he is unable or unwilling to understand the UK position on Brexit,” Conservative MP and former Brexit Minister David Jones told The Sun.

“His stance is unsympathetic to the UK’s people’s wish to recover their independence.”

With the US election now just over three weeks away, most opinion polls show Mr Biden on track for a landslide victory.

The Real Clear Politics average currently has the Democrat ahead of the Republican by nearly 10 percentage points nationwide.

Polling analysis website FiveThirtyEight currently puts the chances of a Biden victory at 86 per cent.

Mr Biden said at a campaign stop over the weekend that “chicanery” at the voting booth was the only way he could lose, before walking back his comments after they were interpreted as casting doubt on the legitimacy of the outcome.

“Make sure to vote,” the former vice president told voters in Pennsylvania. “Because the only way we lose this is by the chicanery going on relative to polling places.”

Mr Biden said he was referring to comments by Mr Trump encouraging supporters to “go to polls and watch very carefully”.

The US President has repeatedly raised concerns of looming election chaos due to the large number of mail-in ballots this year.

Democrats have warned the public not to expect a definitive result on election night, with some even saying it may at first appear Mr Trump has won in a landslide only for his lead to be chipped away as all the votes are counted in the subsequent days.

Before leaving Pennsylvania, Mr Biden clarified his comments, saying they were “taken a little out of context”.

“I’m going to accept the outcome of this election, period,” he said. “What I was referencing is the attempts that are made to try to influence and scare people from voting. You should not pay attention to them.”

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