The head of the United Kingdom’s domestic intelligence agency MI5 has warned of escalating hybrid threats from both Iran and Russia, with the agency currently allocating more resources to countering state threats than during the Cold War. In his annual address, MI5 Director General Sir Ken McCallum highlighted a significant shift in Iran’s tactics this year, noting increased attempts to target military sites within the UK.
McCallum pointed to an incident near RAF Fairford in Gloucestershire last month, which UK Prime Minister Andy Burnham described as "almost certainly" linked to Iran’s Islamic Revolutionary Guard Corps. RAF Fairford has been used as a base for US bombers involved in strikes against Iran, and the suspected attack led to a heightened security response and the temporary withdrawal of US aircraft. While McCallum declined to provide detailed comments on the ongoing investigation, he said such Iranian threats to military locations were part of a broader pattern seen worldwide.
Iran's activities have reportedly resulted in more than 50 arrests over the past year in connection with operations linked to its interests, reflecting a more aggressive posture in the UK. McCallum characterized this year as a turning point, with Tehran aiming at higher-value targets compared with prior years.
Russia remains, according to MI5’s assessment, the principal aggressor in hybrid warfare efforts against the UK and its allies. Over the past decade, threats from state actors have quadrupled, demanding a scale of intelligence operations comparable to MI5’s counterterrorism workload. McCallum described Russian efforts as attempts to wage conflicts below the threshold that would trigger NATO’s Article 5 mutual defense clause.
He noted that Russia is increasingly relying on individuals recruited via online platforms rather than professional intelligence officers, many of whom have been expelled in recent diplomatic disputes. These operatives are often engaged through cryptocurrency payments or other online means to conduct covert activities in the UK.
McCallum also raised concerns about the misuse of artificial intelligence, particularly its potential to aid terrorists in reconnaissance and attacks, including AI-enabled drones. Of greatest concern to the agency is AI’s possible impact on bioweapons development or the creation of novel pathogens. To address these emerging risks, MI5 is establishing an AI Threat Assessment Centre to coordinate evaluations of related threats.
UK Foreign Secretary Ed Miliband echoed the broader security concerns, stating that Europe’s resilience is being tested by Russia’s hybrid tactics amid the ongoing war in Ukraine. He also referenced recent tensions in transatlantic relations following a diesel supply deal between the United States and Russia.
While Russia has denied involvement in hostile acts within Britain, European intelligence agencies have pointed to incidents such as a drone attack attempt on a cargo plane in Germany and cyberattacks on Polish energy infrastructure as examples of Moscow’s hybrid operations.
Overall, MI5’s current intelligence picture portrays a complex and intensifying security environment in which state-sponsored threats and technological challenges converge.