Andy Burnham has said UK authorities are “clear” that there was Russian interference in the Brexit vote: this is the first time a prime minister has confirmed Kremlin involvement in the 2016 referendum.

Burnham, speaking on The Rest Is Politics podcast, to be released on Monday, opens up the possibility of greater government transparency over allegations of Russian interference, after years in which Downing Street has declined to confirm what UK authorities knew about the part the Kremlin might have played in 2016.

The Observer was the first to reveal concerns arising from a series of meetings between Russian officials and senior figures at the Leave. EU campaign, including mega donor Arron Banks. It is not suggested Banks or any other Leave. EU figure was engaged in wrongdoing.

Separately, there have been widespread allegations that Russian government agencies used troll factories and fake internet accounts to manipulate social media and influence British public opinion in favour of leaving the EU in the run-up to the referendum.

Burnham, who last week met the German chancellor, Friedrich Merz, in Berlin, said the pair discussed the growing risks posed by hostile states, and that his counterpart “was saying to me that the AfD [Alternative für Deutschland] are clearly linked to Russia – funded, I believe”.

Speaking on the podcast, he added: “There is certainly misinformation, disinformation that is emanating from Russia into German politics… But 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.

“I mean, these things are important now to put clearly on the record and, I believe, help voters in Germany and France understand that some of this politics is instigated via our enemies, namely Russia.”

Burnham said the country had been “too much on the back foot”, which meant voters had not been “informed… sufficiently about the extent to which people are seeking to disrupt the political process from overseas”.

Speaking at the UN a fortnight ago, Burnham touched on Russian interference in UK democracy without discussing the Brexit vote. He said: “We have evidence that they tried to interfere with the 2019 general election. We also know that they have tried to stoke tensions and unrest in the wake of horrific events.”

The 2020 Russia report, written by parliament’s intelligence and security committee (ISC) and heavily redacted before publication, said it was unable to reach a conclusion because: “We have not been provided with any post-referendum assessment of Russian attempts at interference.” The ISC’s request for a further assessment to be carried out, with an “unclassified summary” to be made public, was rejected by the Boris Johnson-led government of the time.

The 2016 referendum was outside the scope of Philip Rycroft’s recent review of foreign financial influence and interference, although the senior civil servant noted that the UK was “a target of long-term strategic foreign interference and espionage from elements of the Russian, Chinese and Iranian states”.

In 2018, The Observer revealed that leaders of Leave.EU had held multiple meetings with high-ranking Russian officials between November 2015 and 2017, and made a trip to Moscow in February 2016.

Banks has repeatedly denied any involvement with Russian officials, or that Russian money played any part in the Brexit campaign.

Later in 2018, the then Sunday Times journalist Isabel Oakeshott suggested that the Kremlin might have “literally struck gold” in forging a relationship with Banks – who would go on to become the biggest single donor to Brexit – and fellow Leave.EU campaigner Andy Wigmore. “My analysis is that Banks and Wigmore were shamelessly used by the Russians,” she added.

Banks was investigated by the Electoral Commission, which referred the matter to the National Crime Agency (NCA).

Questioned over the “true source” of £8m loaned to the Leave.EU campaign, Banks told the BBC: “There was no Russian money and no interference of any type. I want to be absolutely clear about that. The money came from Rock Services, which was a UK limited company.”

The NCA subsequently found “no evidence” of criminal offences. Banks threatened to take the Electoral Commission to court for defamation in October 2019, before the two sides settled the following year.

A Downing Street spokesperson declined to comment on the nature of the prime minister’s briefing but said: “National security is the first duty of any government – we are focused on ensuring our citizens and our institutions are protected from foreign powers and their proxies seeking to threaten lives and undermine our democratic values.”

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