Communications and Multimedia Minister Salleh Said Keruak has accused whistleblower site Sarawak Report of stalking and harassing Prime Minister Najib Abdul Razak's wife Rosmah Mansor in London.

In a blog post last night, Salleh claimed the website had demonstrated "an absolute lack of decorum and manners".

"They shouted slanderous allegations that are nothing but a pack of lies while saying that freedom of the press allows them to say whatever they like.

"We would expect people from so-called civilised England to at least show respect to the wife of a foreign prime minister, but apparently diplomacy is reserved only for their own kind," he said.

It is not clear what had exactly transpired, but the blog posting coincided with a YouTube video uploaded by blogger Raja Petra Kamaruddin titled "Sarawak Report stalks and harasses Rosmah Mansor in London, 8th May 2017".

The video shows three individuals standing outside a compound of a house in what appears to be London.

One of the individuals, a man, is heard telling the person recording the video that they should not have come to London if they did not want to be photographed.

"You shouldn't come here if you don't want to be exposed to proper journalism, and the focus of the world's attention on what is the biggest financial crime of the modern era.

"You should pay back the money to the Malaysian people because I know they need it," the man added.

It is not known who these individuals are.

Malaysiakini has contacted Sarawak Report editor Clare Rewcastle-Brown and Rosmah's aide Rizal Mansor for comment.

Sarawak Report has been claiming that Najib had misappropriated public funds through 1MDB for personal gain - allegations which the prime minister vehemently denies.

Rosmah arrived in the United Kingdom with 32 Permata students and six teachers last Thursday and will be there until Wednesday.