MI5 says Russia tried to interfere in Brexit vote but failed to affect result

MI5 chief Ken McCallum said on Oct. 13, 2026, Russia attempted to interfere in the 2016 Brexit referendum through biased RT and Sputnik coverage and fake accounts largely on X. He called the tactics not particularly sophisticated or successful, with no impact on the result. He endorsed Prime Minister Andy Burnham’s account and warned debate gives Russia a propaganda victory.