Donald Trump has raised the stakes in an ongoing feud with the spouse of one of his closest advisers – describing him as a “loser” and the “husband from hell”.

George Conway, the partner of White House aide Kellyanne Conway, has long criticised the US president – accusing him of lying and even claiming that Mr Trump is mentally unfit for office.

Following a barrage of ill-tempered tweets sent by Mr Trump over the weekend, Mr Conway accused the president of having narcissistic personality disorder.

The president replied: “George Conway, often referred to as Mr. Kellyanne Conway by those who know him, is VERY jealous of his wife’s success & angry that I, with her help, didn’t give him the job he so desperately wanted. I barely know him but just take a look, a stone cold LOSER & husband from hell!”

Mr Conway then posted a brief response of Twitter, simply writing: “You. Are. Nuts.”

Kellyanne Conway walks towards the West Wing of the White House
Image:Kellyanne Conway is one of the president’s closest allies

In 2017, it was reported that Mr Conway was in the running for a job at the Department for Justice, but he later withdrew himself from contention. The president insists the lawyer was actually turned down for the role.

Following Mr Trump’s latest Twitter outburst, Mr Conway told Reuters: “The president seems determined to prove the point I’ve been making.”