Prime Minister Andy Burnham told The Rest Is Politics podcast on Sunday that Russia interfered in the 2016 Brexit vote, a claim he first made after taking office in July.
Burnham said he had asked Downing Street whether there had been interference and received a clear answer that "yes, there was." He did not provide specific evidence or explain how Russia allegedly meddled.
The Russian Embassy in London declined to comment on the allegation. Moscow has repeatedly denied any role in the referendum, calling the claim part of anti‑Russian hysteria.
The statement marks a stark shift from former Prime Minister Boris Johnson, who in 2020 denied any interference, and from a 2020 Intelligence and Security Committee report that found no conclusive evidence of meddling.
Burnham warned voters in France and Germany that they too face Moscow‑backed efforts to disrupt their politics, and said he could campaign for a UK return to the EU at the next general election.
The announcement has already prompted opposition MPs, including from the Liberal Democrats and the SNP, to demand a fresh parliamentary inquiry into foreign influence on UK elections, with the next session of the Commons slated to address the issue next week.