Threats from foreign adversaries have quadrupled in the last decade, and MI5 now devotes more resource to state threats than it did during the Cold War, the MI5 chief Sir Ken McCallum said, BBC News reported. He was delivering the agency’s annual threat update in London on Tuesday.
Counter-terrorism and state-threat work are now “pretty much of equal scale” inside the agency, he said, according to the BBC. He called that a “huge shift”.
Russia and the Brexit Question
Russia has stopped short of conventional conflict with Nato and is trying to unsettle European countries, Sir Ken said in his speech, as reported by BBC News. Almost 1,000 expulsions since the invasion of Ukraine have left the Kremlin paying proxies, he said.
“So we see them scrambling to pay criminals to do their bidding,” he said in the speech, according to the BBC. “These are not the actions of a great power with the strategic upper hand.”
Questions from reporters followed the speech. Asked about Brexit, Sir Ken said attempts from Moscow were “not new news”, BBC News reported. He drew a line between “interference attempted” and “outcome achieved”, and said the 2016 result was “not in dispute”.
“I am a little bit anxious that we don’t play into our adversaries’ hands by making these trolls look 10ft tall,” he told reporters, according to the BBC.
Iran and Harder Targets
There have been 50 arrests in the last year over Iran-linked activity, BBC News reported. Much of that activity was aimed at Jewish communities and at “harder targets, like military sites”, according to the BBC.
He told reporters afterwards that the RAF Fairford incident was “not unique”, the BBC reported. The men who drove to the village next to the base were released on police bail after no bombs or explosives were found, The Guardian reported.
Artificial Intelligence
MI5 has launched an AI Threat Assessment Centre to “separate the bluster from the realities”, BBC News reported.
Sir Ken said MI5 had caught terrorists seeking to exploit AI, including with drones, according to the BBC. He said the bioweapons threat from AI was “not yet realised”.
“Put at its simplest, human history has given us no experience of facing an actor which is smarter than we are”, he said in the speech, as reported by the BBC.
A New Era of National Security
“We have again entered a new era of national security,” McCallum, MI5’s director general, said, according to The Guardian.
The UK terrorism threat level was raised to severe in April, for the first time in five years, BBC News reported.
Sir Ken also addressed extremism in his speech. “Over the last year the most marked trend has been an increase in cases where extremist versions of anti-immigration and anti-Muslim grievance are tipping into terrorist intent,” he said, according to the BBC.
MI5 investigated a radicalised extreme right-wing 13-year-old in the UK in recent months, the BBC reported.
More reporting from Britain and beyond is in our International news section.
Sources: BBC News, “MI5 tackling more state threats than during Cold War, warns intelligence chief”, 13 October 2026 (https://www.bbc.co.uk/news/articles/c60rl5vwpk02o); The Guardian, “Rightwing extremists increasingly likely to consider terrorist attacks, MI5 chief says”, 13 October 2026 (https://www.theguardian.com/uk-news/2026/oct/13/rightwing-extremists-increasingly-likely-to-consider-terrorist-attacks-mi5-chief-says)
Photo: Txllxt TxllxT, CC BY-SA 4.0, via Wikimedia Commons.
Thames House on London’s Millbank, seen through its railings in June 2011. A file view of the building rather than this week’s address.