British Prime Minister Andy Burnham has said it is clear that Russia interfered in the 2016 referendum on leaving the European Union, becoming the first UK prime minister to say so openly. Speaking on The Rest Is Politics podcast, released on Sunday, he said he had asked on arriving at Downing Street whether Moscow had interfered. "I've had the clear answer that yes, there was," he said.

Burnham did not say who gave him that assessment, what evidence it rested on, or whether any interference affected the result. Britons voted 52% to 48% to leave the EU in 2016, a decision that triggered the country's deepest political crisis since World War Two. Russia has repeatedly denied meddling in Western democracies, accusing Britain of "anti-Russian hysteria". The Russian embassy in London did not immediately respond to a request for comment on the latest remarks.

The comments depart from the line of earlier Conservative governments. Boris Johnson, who campaigned to leave the EU, said in 2020 there was no evidence of Russian interference in the referendum. That year, parliament's cross-party Intelligence and Security Committee criticised the government and intelligence agencies for failing to seek a full assessment of Russian activity, despite evidence of attempts to influence British politics through state-backed media and social media accounts. It contrasted this with the investigation the United States carried out after its 2016 presidential election. The committee did confirm that Russia had tried to influence Scotland's 2014 independence referendum, in which voters rejected independence, and said that whether a hostile state tried to influence a democratic process mattered regardless of whether it succeeded.

Burnham framed his remarks as a message to other European democracies. He said putting such matters on the record would help voters in Germany and France understand that "some of this politics is instigated via our enemies, namely Russia", and that Britain had been "too much on the back foot" in informing the public. He said he discussed the far-right Alternative für Deutschland (AfD) with German Chancellor Friedrich Merz in Berlin last week, and that Merz raised concerns about the party's links to Russia. Burnham said Merz told him the AfD was "clearly linked to Russia – funded, I believe". The Guardian notes that last month he told the UN General Assembly there was evidence Moscow had tried to interfere in the 2019 UK general election.

The government is developing a National Centre for Information Defence to detect and disrupt hostile state information campaigns, and Downing Street says it is working with Germany on a partnership to counter hybrid threats. The remarks also come as Burnham has reopened the Brexit debate: last month he said Britain could consider rejoining the EU and that he might campaign for it at the next general election, arguing that leaving had failed to deliver "taking back control" and left the UK weaker economically and on immigration.