Donald Trump will ‘unleash all-out struggle’ on Keir Starmer if he wins US Presidential race after row over Labour serving to out his rival Kamala Harris

Donald Trump will unleash ‘all-out war’ on Sir Keir Starmer if he returns to the White House, according to senior Conservative figures who have been in contact with the former US President’s campaign team.

The Tory party sources said that revelations about the Labour Party’s alleged interference in the US election on behalf of Trump’s Democratic opponent Kamala Harris would have far-reaching consequences if he ends up victorious in the vote in ten days’ time.

A source told The Mail on Sunday: ‘Do not underestimate the damage Starmer has done to relations with the US – the Trump team are ready and waiting to unleash all-out war on him, because he is perceived as anti-American and a whingeing, liberal bore’.

The Trump campaign has lodged a complaint with the US elections watchdog over ‘illegal foreign national contributions’ after it emerged that Labour’s head of operations, Sofia Patel, asked party staffers if anyone would be willing to travel to the US to ‘help our friends across the pond elect their first female president’.

Senior Labour figures, including Morgan McSweeney – now the No10 chief of staff – and director of communications Matthew Doyle attended the Democratic National Convention in August. The delegation included Hollie Ridley, then Labour’s executive director of nations and regions, and senior aide Sheila Murphy.

Donald Trump will unleash ‘all-out war’ on Sir Keir Starmer if he returns to the White House , according to senior Conservative figures who have been in contact with the former US president 

It comes after the Trump campaign lodged a complaint with the US elections watchdog over ‘illegal foreign national contributions’ after it emerged that Labour activists were campaigning for his Democrat rival Kamala Harris 

Ms Ridley has since been appointed as Labour’s general secretary, replacing David Evans – who was also on the trip. All were closely involved in Labour’s general election campaign.

The latest polling puts Harris ahead overall by just over one per cent – but the Electoral College system could still favour Trump, even if he is behind in the popular vote.

A significant majority of bets placed on the election in the past week in America have been on Trump.

Sir Keir has tried to play down fears that the spat could derail Britain’s relationship with America if Mr Trump wins. 

Speaking at the Commonwealth heads of government summit in Samoa, he said: ‘I met President Trump just a few weeks ago in New York. We had dinner together for two hours. We wanted to make sure we get to know each other. The fact that a few Labour volunteers went in this election, as they have done in every previous election, in previous elections, as political activists from all political parties in pretty much every election year after year after year, needs to be put into its proper perspective.’

He added: ‘I’ve got a good relationship with President Trump. I will work with whoever is elected.’

Trump’s deputy general counsel argued in a letter to the Federal Election Commission on Tuesday that Labour’s campaigning effort was part of a ‘far-Left’ plot to thwart his campaign.

The complaint states that a ‘reasonable inference’ could be drawn that Labour was involved in the organisation of the trip, despite the party denying this.

The letter also accused the officials of advising the Harris campaign at the convention, which it said was a breach of rules that do not allow foreigners to make ‘contributions’ in the US.

British Prime Minister Keir Starmer attends a press conference during the Commonwealth Heads of Government Meeting in Samoa today