Trump made his comments in a speech to the UN General Assembly in New York on Tuesday in which he took aim at Sadiq Khan, the first Muslim to become mayor of London.

“I look at London, where you have a terrible mayor, terrible, terrible mayor, and it’s been changed, it’s been so changed,” Trump said.

“Now they want to go to sharia law. But you are in a different country, you can’t do that,” he added, referring to the Islamic law code based on the teachings of the Koran.

Starmer told reporters in London there were “a few things” on which he and Trump disagreed, despite a successful and amicable state visit by the president earlier this month.

“This is one of them. The idea of the introduction of sharia law is nonsense, and Sadiq Khan is a very good man and actually driving down serious crime,” he said.

“We had a good state visit last week, but on this I disagree with him… the sharia law comments were ridiculous,” he added.

Khan, from Starmer’s centre-left Labour Party, has had a long-running feud with Trump.

In office since 2016, he criticised Trump that year over the then-presidential hopeful’s proposed travel ban for people from some Muslim-majority countries.

Before Trump’s first state visit to London in 2019, Khan also likened him to “European dictators of the 1930s and 40s”.

Following Trump’s latest broadside, Khan branded the president “racist, sexist, misogynistic and Islamophobic”.