Russia did attempt to interfere in the 2016 Brexit referendum, the director general of MI5 said on Tuesday, though he made clear that this did not amount to Moscow having shaped the result.
Ken McCallum said the interference took the form of social media activity and television reporting. Speaking at his agency’s annual threat update, he endorsed remarks made by Andy Burnham, who had raised the subject over the preceding two days, but warned that prolonging the argument had handed the Kremlin an unnecessary propaganda win.
According to McCallum, the Russian-owned English-language outlets RT and Sputnik “came in pretty strongly around the time of the referendum”, carrying slanted coverage hostile to migration and to the EU.
He identified a second attempted channel of interference involving internet trolls — an unspecified number of fake social media profiles, working mainly on X, that tried to sway the vote.
Neither method was especially sophisticated and neither met with much success, the MI5 chief said, drawing a sharp distinction between what may have been attempted and what actually resulted.
Both forms of interference have been documented before in research published in the years following the referendum. The digital campaign group 89up reported that RT and Sputnik carried 261 largely misleading articles foregrounding immigration and other anti-EU themes, generating 134m potential page impressions.
Further studies have described a “troll army” of state-linked Russian accounts posting about the referendum in the run-up to the vote, with estimates of the numbers involved varying widely between 54 and 150,000.
Burnham first revisited the question on Sunday in a podcast interview, at which point it was unclear whether the prime minister had been shown new intelligence on a topic that had been widely treated as settled. “I asked the question coming to Downing Street: ‘Was there interference in the 2016 referendum from Russia?’ And I’ve had the clear answer that yes, there was,” he said, suggesting he had received a discussion or briefing.
He stepped back from the claim a day later when the Conservatives challenged him on whether he now regarded the Brexit vote as illegitimate, and offered the Commons no further information.
Downing Street said on Tuesday that Russian interference in the 2019 general election had been confirmed and that it was “inconceivable that they didn’t in 2016”. The prime minister’s spokesperson added: “We don’t believe it was successful in the British referendum in 2016.”
McCallum said Russia stood to gain if the controversy continued for days longer. “It is up to us how far we allow our adversaries to divide us,” he said.
Sustained attention, he added, gave the impression that Kremlin disinformation had been more effective than it was, and he voiced concern that another few days of debate would leave Russian trolls — who appeared to have achieved little at various points over the years — delighted to be front-page news again, despite the limited effect of their efforts.
COMMENTS