Sir Ken McCallum, director general of MI5, said the agency is now devoting roughly as much effort to countering state-backed threats as it does to traditional counter-terrorism work, a notable shift for an organization historically built around stopping bombings and extremist plots. He singled out Russia and Iran as the two states driving this change, pointing to their intelligence services' growing willingness to conduct hostile operations on British soil.
The warning comes amid years of rising friction between London and Moscow, strained further by Russia's war in Ukraine, and persistent tension with Tehran over its regional activities and alleged plots against dissidents and critics based in the UK. Western security agencies have repeatedly accused both governments of sponsoring sabotage, surveillance and intimidation campaigns abroad, though neither Moscow nor Tehran typically acknowledges such operations.
McCallum also flagged artificial intelligence as a fast-emerging complication for security services, a departure from the more familiar categories of state and terrorist threats. While he did not detail specific AI-enabled plots, his remarks reflect a broader unease among Western intelligence officials that the technology could be exploited to accelerate disinformation campaigns, cyberattacks or other covert operations, while also straining agencies' ability to detect and attribute them.
The acknowledgment that state threats now rival terrorism in scale marks a significant recalibration for MI5, which spent two decades after the September 11 attacks oriented primarily around jihadist and later far-right extremist violence. Officials have in recent years quietly expanded resources devoted to counter-espionage, but McCallum's comments represent one of the clearest public statements yet that this shift has become structural rather than temporary.
The remarks are likely to feed into ongoing debates in Westminster over the UK's preparedness for hybrid warfare — tactics blending cyber intrusion, disinformation and physical sabotage — and over how security agencies should adapt their funding and legal powers as technology reshapes the threat landscape. No new policy announcements accompanied the comments, but they are expected to inform upcoming government reviews of national security strategy and the resourcing of intelligence agencies.