British lawmakers and members of the upper house of parliament are exerting pressure on the government of Rishi Sunak to proscribe Iran’s Revolutionary Guard Corps as a terrorist organization, saying it would be a step towards restoring stability to the Middle East.

In a letter to the Prime Minister, more than 60 lawmakers from the lower house of parliament and members of the House of Lords said “given the ongoing conflicts in the Middle East, it is now more urgent than ever to proscribe the IRGC,” according to Reuters.

“We call upon our government to recognize the urgency of proscribing the IRGC as a terrorist organization and proceed to do so. Such a decision would constitute a significant step towards peace, stability, and justice in the Middle East and beyond,” read the letter, signed by senior Conservatives such as Iain Duncan Smith, David Davis and David Jones.

Proscribing the IRGC as a terrorist group would mean it would become a criminal offense in Britain to belong to the group, attend its meetings or carry its logo in public.

The IRGC is already subject to British sanctions for violating human rights and for their missile activities, in addition to being responsible for supplying Russia with kamikaze drones that were used in the Ukrainian war.

Last month, British media outlets said British counter-terrorism officers are monitoring closely if Iran will try to exploit the Israel-Hamas war for its own ends in the UK, amid wider anxieties that Tehran is an increasing security menace to dissidents and critics.

The officers are also monitoring more than 10 mosques, groups and educational institutions that are linked to Iran’s IRGC around the country.

In remarks specifically about Iran, Ken McCallum, MI5’s director, said last month that London had “been concerned” about its behavior within Britain “for a long time,” with the current Middle East situation heightening those concerns.

“There clearly is the possibility that profound events in the Middle East will either generate more volume of UK threat and/or change its shape in terms of what is being targeted, in terms of how people are taking inspiration,” McCallum said.

“In particular, the last 18 months or so have been a particularly intensive phase of Iran-generated threat on UK soil,” he added.

Last November, the MI5 director said Iran’s “aggressive intelligence services” were actively targeting Britain and had made “at least 10” attempts to “kidnap or even kill” British or UK-based individuals since January.

By February this year the figure had increased to 15.

In August, a British media report said the British Home Secretary Suella Braverman and her team believe that the Iranian Revolutionary Guards Corps is the biggest threat to the country’s national security.

“The Iranian threat is the one that worries [the UK] the most,” a source close to the home secretary told The Sunday Times. “It’s a big issue because they are getting much more aggressive and their appetite is increasing … They are very defensive to anyone challenging their regime”, the source added.

In January, a foreign office minister said Britain was actively considering proscribing the IRGC as a terrorist organization but had not reached a final decision.

Last February, The Times reported that the government had “temporarily” halted a plan to classify the Revolutionary Guards on the terrorist list, after the opposition of Foreign Secretary James Cleverly, despite the insistence of the Home Secretary and Security Minister Tom Tugendhat.

Two weeks ago, The Guardian said the Foreign Office believes that the plan would lead to the expulsion of the British ambassador to Tehran and, as a result, the loss of the UK’s remaining influence in Iran.