Donald Trump has said Andy Burnham “has got a big job ahead of him, but he will be able to do it” and pledged that the US “will be there to help”.
In an upbeat message on his Truth Social platform, the president also wished the new Prime Minister “good luck and godspeed”.
The early endorsement of the former Greater Manchester mayor by the American leader comes after the pair spoke on the phone within an hour of the Makerfield MP arriving in Downing Street.
It will also assuage fears after the Republican president previously described Mr Burnham as “extremely liberal” and “mayor of a town”.
In addition it signals a fresh start in the transatlantic partnership after relations with Sir Keir Starmer grew increasingly fractious over the Iran war.
Mr Burnham was buoyed in Mr Trump’s eyes after reports he could back new oil and gas drilling in the North Sea, which the president has championed.
Mr Trump said at the weekend said people in Aberdeen would be “dancing in the streets” at such a move, albeit unconfirmed.
The president, a vocal supporter of fossil fuels, insisted further drilling in the North Sea would “make the United Kingdom, from a Poverty Stricken Disaster, to one of the Richest Countries anywhere in the World”.
In his Truth Social Post, Mr Trump said: “I had a very good conversation with the new Prime Minister of the United Kingdom, Andy Burnham.
“We discussed many subjects, including the outstanding relationship we have had with the UK.
“We will be meeting in the not too distant future for topics of mutual interest.”
He added: “The Prime Minister has got a big job ahead of him, but he will be able to do it and, of course, the USA will be there to help!
“We discussed North Sea Oil, Trade, the Military Alliance, Demining of the Hormuz Strait, and many other topics.
“The call was interesting, and went very well. I wished Prime Minister Burnham, GOOD LUCK AND GODSPEED!”
The importance of the call had earlier been hailed by the British embassy in Washington.
In a post on X, the diplomatic mission said: “Within an hour of taking office, Prime Minister Andy Burnham… spoke with President Donald Trump, underscoring the importance of the UK/US partnership from day one.
“The leaders discussed shared priorities and agreed to remain in close contact.”
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