Lord Cameron will meet with Mr Trump, then make his way to Washington DC for discussions with Mr Blinken, other figures from the Biden administration and members of Congress, a Foreign Office spokesperson said.

"His talks [in Washington] will focus on a range of shared US-UK priorities, including securing international support for Ukraine and bringing stability to the Middle East," they stated.

The spokesperson played down Lord Cameron's visit to see former US president Mr Trump, who is seeking a return to the White House in this November's US election.

"It is standard practice for ministers to meet with opposition candidates as part of their routine international engagement," they said.

Lord Cameron is not scheduled to meet current US President Joe Biden.

On Monday, the foreign secretary issued a plea for the US to follow through with a package of aid for Ukraine.

In an op-ed penned with his French counterpart Stephane Sejourne, he wrote: "Ukraine must win this war. If Ukraine loses, we all lose.

"The costs of failing to support Ukraine now will be far greater than the costs of repelling Putin."

In a social media message shared last week, Lord Cameron said that he intended to use his US visit to pressure America to help fund Ukraine's war efforts.

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"Britain's put forward its money for Ukraine this year. So's the European Union," he wrote on X. "America needs to do it. That is blocked in Congress.

"Speaker Johnson can make it happen in Congress. I'm going to go and see him next week and say we need that money, Ukraine needs that money.

"It is American security, it's European security, it's Britain's security that is on the line in Ukraine, and they need our help."

Meanwhile, Trump has "frequently boasted" that he could "negotiate a peace deal between Russia and Ukraine within 24 hours if elected", according to a US media report published on Monday.

If he makes a return to the Oval Office, Mr Trump will press Ukraine to give up their territory and has proposed that Ukraine should cede Crimea and the Donbas border region to Russia, the Washington Post said.

The policy would "reward Vladimir Putin" and "condone the violation of internationally recognised borders by force", foreign policy experts have warned.