A UK-based Iranian broadcaster has said it has been forced to move to the US over threats from Tehran and fears for the safety its journalists.

The relocation of Iran International TV to Washington DC follows warnings from the Metropolitan Police that there remain “serious” and “grave” concerns about “hostile intentions of foreign states”.

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

It comes after a man was arrested on Monday in the same area and charged with terrorism offences related to the surveillance of the company’s headquarters.

Mahmood Enayat, general manager of Iran International TV, said in a statement: “I cannot believe it has come to this.

“A foreign state has caused such a significant threat to the British public on British soil that we have to move.

“Let’s be clear, this is not just a threat to our TV station but the British public at large.

“Even more this is an assault on the values of sovereignty, security and free speech that the UK has always held dear.

“Day and night our journalists strive to deliver the 85 million people of Iran and its diaspora the independent, uncensored news they deserve.

“We refuse to be silenced by these cowardly threats. We will continue to broadcast. We are undeterred.”

The Met said police and MI5 have foiled 15 plots since the start of 2022 to either kidnap or kill UK-based individuals perceived as enemies of the Iranian regime.

The force had ramped up security measures focused on the area surrounding the studios of the Persian-language broadcaster, which included an overt armed policing presence in the vicinity.

But head of counter-terrorism policing (CTP), assistant commissioner Matt Jukes said in a statement: “In light of the ongoing investigation that follows the arrest of a man last weekend in that area, and despite extraordinary security measures, we still have serious concerns for the safety of people working at this company.

“This has led to us giving further advice and the company is now relocating.

“We would like to thank the company for their ongoing understanding with this as we continue to support them.”

He added: “We also appreciate that talking to a media company about moving their operations from a particular location, even though it is due to grave safety concerns, is exceptional.

“The advice to relocate has not been given lightly.

“The situation that journalists face around the world and the fact that some journalists face such hostile intentions of foreign states whilst in the UK is a challenging reality that we are determined to confront.”

Iran International has been one of the most prominent sources of news about the recent wave of anti-Government protests sweeping the country.

The demonstrations were triggered by the death of 22-year-old Mahsa Amini last September after she was detained by police in the capital for allegedly not adhering to Iran’s Islamic dress code.

Protests have taken place in more than 125 cities, with at least 270 people killed and nearly 14,000 arrested, according to the group Human Rights Activists in Iran.

The UK Government responded to the broadcaster’s move by condemning the “lack of respect for basic rights” demonstrated by the Iranian regime.

A 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.”