Britain has announced that it will designate Iran’s Islamic Revolutionary Guard Corps (IRGC) as a threat to national security, marking a major escalation in its efforts to counter hostile state-backed activity and foreign terror networks operating on British soil.

Home Secretary Shabana Mahmood said on Monday that the government would use new counterterrorism powers to outlaw support for the IRGC — the elite arm of Iran’s armed forces responsible for overseas operations and the coordination of proxy groups — citing its alleged role in terror plots, death threats, and intimidation campaigns targeting the United Kingdom. Under the measures, expressing support for, promoting, or assisting the group will become a criminal offense punishable by up to 14 years in prison.

Alongside the IRGC, the government will proscribe two other organizations: the Islamic Movement of Companions of the Right (IMCR), an Iran-backed group that has claimed responsibility for a string of attacks on Jewish and Israeli-linked sites in Britain, and the GRU Volunteer Corps, a network controlled by Russia’s military intelligence agency, the GRU, which British officials say has a long record of covert operations against the UK and its allies.

“Iran and Russia are using proxies and thugs to do their dirty work on our shores,” Mahmood wrote in a statement to Parliament. “I have rapidly designated three groups so those working for them will be tracked down and put behind bars.”

According to the government, the IMCR publicly claimed responsibility for seven attacks this year at locations linked to Jewish and Israeli communities and a Persian-language media outlet, among them an arson attack on four ambulances in the Golders Green area of north London in March. British officials said members of the IRGC’s elite Qods Force “almost certainly” directed the group’s operations across Europe.

The designation places the organizations on a similar legal footing to banned terrorist groups, significantly expanding the government’s ability to disrupt their activities, freeze support networks, and prosecute those accused of aiding them. Those who carry out acts of sabotage, including arson, on behalf of the groups could face life imprisonment.

The measures also grant police and intelligence agencies broader powers to investigate suspected espionage, foreign interference, sabotage, and politically motivated violence linked to hostile state-backed organizations. By removing the requirement for prosecutors to prove a direct connection to a foreign government in every case, the legislation is expected to make it easier to bring charges and respond more quickly to national security threats.

The three groups are the first to be designated under the National Security (State Threats) Act, which received royal assent last week. Parliament is expected to approve the specific designations later this week. The move brings the UK closer to allies that have already listed the IRGC as a terrorist organization, including Australia, Canada, and the US, as well as the European Union, which added the group to its terror list in January.

British Prime Minister Sir Keir Starmer said the measures reflect the government’s determination to confront hostile foreign actors and strengthen Britain’s defenses against state-backed terrorism.

“We will never let Britain be a playground for states who want to spread fear, division and violence on our streets,” Starmer said. “We have already taken tough action against the Iranian regime and those linked to it, and against Russian operatives and networks targeting our country.” He added that the new powers would make it easier to prosecute and imprison anyone doing such work in Britain.

The announcement follows a sharp rise in Iranian-linked activity abroad since the outbreak of the US-Israeli war against Iran in Feb. 2026, which analysts say has pushed the IRGC to lean more heavily on proxy networks and covert operations beyond the Middle East. MI5 has identified at least 20 potentially lethal Iranian-backed plots against people in the UK over the past year, many of them aimed at members of the Jewish community and Iranian dissidents living in the country.