Mr Lammy, who is the shadow foreign secretary, was speaking to The World With Yalda Hakim on Sky News, and had his previous comments put to him.

If Labour were to win the next election in the UK, and Mr Trump to win the next vote in the US, then Mr Lammy would likely be the government's voice on the world stage.

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In an article in Time magazine in 2018, Mr Lammy wrote: "Trump is not only a woman-hating, neo-Nazi-sympathising sociopath.

"He is also a profound threat to the international order that has been the foundation of Western progress for so long.

"It is because I cherish and champion those values that this Friday, I will march with London against Donald Trump."

But speaking to Yalda tonight, Mr Lammy said: "It doesn't matter who is in Number 10 - you work with the United States."

Asked about his previous comments, he said: "Look, I think all backbenchers of both sides and I know that the current Foreign Secretary David Cameron described him as a misogynist and xenophobic.

"So all of us are going to have a backstory in relation to that. But the truth is, if I have the privilege of becoming foreign secretary, it will be my job to represent the national interests of this country."

He added that he does "worry that Donald Trump was not keen on NATO because I think it's a fundamental plank of European and global security".

He said: "I do worry that Donald Trump and some of the Republican Party have taken a view that the financing and standing by the people of Ukraine, standing by Zelenskyy, is something that America can turn its back on.

"That worries me greatly. And so part of the job of being foreign secretary, if I have the privilege to do that here in the UK, is also to try and persuade and use your influence."

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Mr Lammy went on to say that he and Sir Keir Starmer would do all they could to persuade Mr Trump to stay in NATO if he were to return to the White House.

The shadow foreign secretary added that "of course NATO would survive" if the US left the alliance - but that it would be "a huge strategic mistake for so many people across the world" if the US did depart.

He also said that Labour would hold a strategic defensive review if it takes over to see how to progress with the UK's armed forces.

Asked if a Labour government would provide extra support to Ukraine if a Trump presidency were to withdraw the US's backing, Mr Lammy said he hopes Mr Trump goes to Ukraine to see the country at war.

He added that maybe Mr Trump has "influence on Putin that I have not seen or none of us have yet seen" when it came to claims the 45th president could end the war in 24 hours.

On Israel, Mr Lammy was asked about comments from Israel's prime minister, Benjamin Netanyahu, who has said Israel must retain control over Gaza once the war with Hamas has ended.

Mr Netanyahu also recently spoke out against a two-state solution to Israel-Palestinian tensions.

The shadow foreign secretary said: "I think that it's extraordinary to suggest that there can't be a two-state solution because the consequences of not having a two-state solution is, I think, a one-state solution, in which case you would have to explain how Palestinians and Israelis can live side by side with equality and rights and self-determination.

"I think that's going to be very hard."

He added he feared ruling out a two-state solution meant "the occupation continues, that siege continues and that dire circumstances continue for many, many Palestinian people" in Gaza.

Mr Lammy said: "I think that's unacceptable and that's why Americans and the UK and our allies in Europe, most of the world, recognises that the only way forward is a diplomatic solution, and that must be predicated on two states."

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Asked if Mr Netanyahu should resign, Mr Lammy said: "I have to take the world as it is, not as I would like it to be.

"That is a decision for the people of Israel.

"They must determine who they want to lead their country. Of course, I follow the politics in Israel, but that is a determination for them."