A UK-based Iranian broadcaster forced to move over threats from Tehran has been guarded by armed police and the situation is "getting out of hand", a senior editor has said.

Iran International TV has been forced to relocate its headquarters from west London to Washington DC in the US after police warned of "imminent and credible threats to the lives of their journalists", the station said.

The channel said that it had "reluctantly" closed its west London studios in Chiswick but its staff "refuse to be silenced by these cowardly threats".

Following the decision, editor Niusha Boghrati told Sky News: "The threats have turned into a reality of terrorism.

"That is what the Met Police have been telling us. Threats were so real this time that they had to ask us to move the operation out of the country.

"It was hard to believe.

"The Met Police have been heavily guarding the location of the office in London with armed police, but it seems right now that it is getting out of hand. It was very significant.

"When you enter this arena as a journalist covering the Islamic government you know it is going to have consequences. We have been living with these consequences for several years.

"The threats, the pressure on the journalists is not something new, but the threats of assassination and kidnapping is an extreme that so far we had not experienced."

Scotland Yard revealed that police and MI5 had foiled 15 plots since the start of 2022 to either kidnap or assassinate UK-based individuals perceived as enemies of the Iranian regime.

On Monday, a man was arrested in the area around the TV studio and charged with terrorism offences related to the surveillance of the company's headquarters, police said.

Mr Boghrati said the station's coverage of protests and the "bigger goal" to seek the truth for people in Iran will not stop.

He added: "It has been a challenging time but we have managed to keep the operation going 24/7.

"The bigger goal will keep us all going."

A Home Office spokesperson said: "Media freedom is a vital part of our society and journalists must be able to investigate and report independently without fear.

"We will not tolerate any threat to media organisations or journalists. We know the Iranian regime has established a pattern of this type of behaviour which is completely unacceptable, yet sadly typical of the regime and its lack of respect for basic rights.

"The police are continuing to work in response to this threat. We will continue to use all tools at our disposal to protect individuals in the UK against any threats from the Iranian state."