All recommendations within this article are informed by expert editorial opinion. If you click on a link in this story we may earn affiliate revenue.
JOE Biden has slammed Liz Truss' economic plan as a "predictable mistake" - just weeks after he called the UK his "closest ally."
The meddling US President also said he "was not the only one" who thought the Prime Minister had blundered with her mini-budget.
He made the extraordinary intervention into UK politics during a visit to an ice cream shop in Oregon on Sunday.
Asked for his opinion on Ms Truss' economic policy Biden said: "I wasn't the only one that thought it was a mistake.
"I think that the idea of cutting taxes on the super wealthy at a time when - anyway, I just think - I disagreed with the policy, but that's up to Great Britain to make that judgment, not me."
The move is sure to be met with disapproval from Ms Truss and her team at No10 - with US presidents expected to stay clear of commenting on UK policy.
The Sun columnist and TalkTV host Piers Morgan said: "Wow. Very unusual, and disloyal, for a US President to publicly trash a British Prime Minister like this - and Biden is hardly in a position to lecture anyone else about the economy or leadership..."
Biden has been widely criticised for his own economic policies - with just 32 per cent of the public approving of his handling of inflation, according to a recent poll.
And meanwhile, just 36 per cent approve of his handling of the economy as a whole.
The US economy shrank at a 0.6 per cent annual rate from April through June.
The US President - who looks set for a bruising set of mid terms results - have seen his overall approval ratings lumbering along at just 44 per cent.
Republicans have branded soaring prices in the US while the American economy shrinks as the "Biden recession".
Craig Mackinlay, the Tory MP for South Thanet, compared Biden’s comments to Barack Obama’s warning that Britain would go to the “back of the queue” for a trade deal after Brexit.
He told : "From President Obama weighing in on the Brexit debate in 2016, probably at the request of Downing Street at the time, US presidential interventions into UK politics is a diplomatic line that should never be crossed and rarely ends well.
"I expect he’d felt emboldened by similar behaviour by the IMF, who decided to weigh in on UK taxation policy. I’d recommend that President Biden looked to his own country’s issues rather than a wider international net."
It comes after last month Biden previously hailed Britain as America's "closest ally in the world" when he met Ms Truss at the UN, in New York.
Biden's comments come after Ms Truss announced a humiliating mini budget U-turn after dramatically firing Kwasi Kwarteng as Chancellor.
The embattled PM confirmed that controversial plans to scrap a rise in corporation tax next year have officially been binned.
The backtrack was a massive embarrassment for the government, who have spent weeks defending the policy.
In a tense press conference that lasted less than 10 minutes on Friday, the shaken PM said: "It is clear that parts of our mini budget went further and faster than markets were expecting.
"So the way we are delivering our mission right now has to change. We need to act now to reassure the markets of our fiscal discipline.
"I have therefore decided to keep the increase in corporation tax that was planned by the previous government."
But new Chancellor Jeremy Hunt hinted at yet another U-turn on Saturday as he suggested public spending could go up - despite Truss saying this would not happen just two days ago.
He denied the UK would return to an austerity era but admitted "difficult" decisions needed to be made on spending and tax.
Mr Hunt told : "Spending will not go up as much as people want and there'll be more efficiencies to find and we won't have the speed of tax cuts we're hoping for, and some taxes will have to go up.
"That's the reality of the very challenging situation we face."
