MI5 Warns Russia Iran Far-Right Threats Equal Terrorism

MI5 Director General Ken McCallum has warned that Russia, Iran and far-right threats are now on an equal scale to terrorism in the UK, marking what he called a 'new era' for the security service. Speaking in his annual threat update on 16 October 2025, McCallum said MI5 and police are tackling state threats and terrorism at roughly the same operational intensity, the biggest shift in the agency's mission since the 9/11 attacks. The assessment comes as Britain confronts a more diverse threat landscape, with state actors and extremist groups both active and shaping near-term counterterrorism and intelligence priorities.

What Did MI5's Annual Threat Update Reveal?

McCallum said state threats have quadrupled in a decade, consuming resources comparable to counter-terrorism and more than during the Cold War. The number of individuals under investigation for state-linked activity rose by 35% in the past year. Iran-backed potentially lethal plots exceeded 20 in 12 months, and UK authorities made 50 arrests linked to Iranian hybrid operations. Since 2020, MI5 and police have disrupted 19 late-stage attack plots. Terror remains an ever-present threat, with Al-Qaeda and Islamic State becoming more ambitious. This shift mirrors broader changes in UK national security strategy.

State Threats: Russia, Iran and China

Russia: 'Aggressor Number One'

McCallum called Russia aggressor number one, waging hybrid warfare through cyber-attacks, sabotage and disinformation. After nearly 1,000 expulsions of Russian spies since the Ukraine invasion, Moscow now pays criminals as proxies. Its battlefield gains in Ukraine remain minimal and horrifically costly. The Kremlin's approach highlights the growing role of Russia hybrid warfare in Europe.

Iran's Expanding UK Campaign

Iran has expanded a UK campaign targeting Jewish communities and military sites, including an incident at RAF Fairford. The 50 arrests in a year reflect a sustained effort to carry out violent and deadly plots on British soil. McCallum said the Islamic Republic poses a direct threat to UK interests, a trend that has drawn attention from Iran state threats experts.

China: A Daily Challenge

Chinese actors pose a daily threat through intelligence activity and economic coercion, adding a further layer to the state threat picture. Analysts continue to monitor China espionage UK operations as part of the broader security response.

Far-Right and Terror Threats: A Rising Domestic Challenge

McCallum flagged rising extreme right-wing terrorism, often involving young people radicalised online. One in five of 232 terror arrests last year involved children under 17, underlining the youth dimension of the threat. The UK threat level remains severe, driven partly by the growing reach of far-right extremism UK networks.

AI Supercharges the Threat Mix

McCallum warned that artificial intelligence supercharges the cyber contest, enables AI-enabled drones and tailored propaganda, and could aid bioweapon development. MI5 has already caught terrorists exploiting AI for reconnaissance. In response, he announced a new AI Threat Assessment Centre, part of a wider effort to understand how AI national security challenges are evolving.

What This Means for UK Security Priorities

The annual assessment will shape near-term counterterrorism and intelligence priorities for the UK and its allies. McCallum announced a new Intervention Centre of Expertise within London's Counter Terrorism Operations Centre, aimed at improving early intervention. The update also acknowledged that courts had justly criticised MI5 over false evidence, with a commitment to accountability and independent oversight.

FAQ: Key Questions About the MI5 Threat Update

What did MI5's director general say about Russia?

McCallum called Russia aggressor number one, saying it wages hybrid warfare through cyber-attacks, sabotage and disinformation, often using paid criminal proxies after nearly 1,000 spy expulsions.

How many Iran-linked arrests were made in the UK?

UK authorities made 50 arrests linked to Iranian hybrid operations in the past year, and Iran-backed potentially lethal plots exceeded 20 in 12 months.

Is far-right terrorism increasing in the UK?

Yes, McCallum said extreme right-wing terrorism is rising, with many cases involving young people radicalised online. One in five of 232 terror arrests last year involved children under 17.

What role does AI play in the current threat landscape?

AI supercharges cyber operations, enables AI-enabled drones and tailored propaganda, and could aid bioweapon development. MI5 has caught terrorists using AI for reconnaissance and has created a new AI Threat Assessment Centre.