British police have revealed they had intervened after North Korean embassy officials reportedly told a London hairdresser to take down an advertisement featuring their leader Kim Jong-Un.

Mo Nabbach said two officials identifying themselves as North Korean officials took pictures of his M&M Hair Academy in Ealing, west London.

They then demanded to know his name, his address and ordered him to remove the "disrespectful" poster from the salon window, he told the Evening Standard newspaper.

The poster featured a large picture of Kim's distinctive short-back-and-sides hairdo with the slogan: "Bad hair day? 15 percent off all gent cuts through the month of April."

"I told them this is England and not North Korea and told them to get their lawyers," the newspaper quoted Nabbach as saying.

"The two guys were wearing suits and they were very serious. It was very threatening."

Nabbach, who is also a fashion photographer, said he had since removed the offending picture.