Dominic Cummings has accused Boris Johnson of lying over his denials that he ignored security concerns to ensure Evgeny Lebedev received a peerage.
The newspaper proprietor, whose father is an ex-KGB agent, became Lord Lebedev of Hampton and Siberia in December 2020.
Johnson has insisted it is “simply incorrect” to suggest he personally intervened to ensure the peerage went through.
According to The Sunday Times, security officials recommended that Lebedev’s peerage be turned down.
In March 2020, the House of Lords Appointments Commission, which vets peerages, reportedly wrote to Johnson advising him not to grant Lebedev – who owns the Evening Standard and Independent newspapers – a seat in the Lords on security grounds.
By June, however, those security concerns were dropped and Lebedev’s ennoblement was approved.
Asked about the allegations that he was personally involved in the process, the prime minister said: “That is simply incorrect. But what I can tell you is, it suits Putin’s agenda to try to characterise this as a struggle between the West and Russia.
“It suits his agenda to say that the UK, that we in Nato countries, are anti-Russia, European countries are now anti-Russian.”
But writing on his blog, Cummings – who was once the prime minister’s top adviser – said: “I was in the room when the PM was told by Cabinet Office officials that the intelligence services and other parts of the deep state had, let’s say, serious reservations about the PM’s plan.
“I supported these concerns and said to the PM in his study explicitly that he should not go ahead. He was very cross and as he does when cross he blustered nonsense.”
Cummings said Johnson “got a stooge to creep into the Cabinet Office labyrinth and cut a deal”.
“I’m confident in predicting nobody would swear under oath the PM is telling the truth – including the PM,” he added.
Labour leader Keir Starmer has called for a senior parliamentary committee to investigate the claims Johnson pushed for the peerage, despite security concerns.
Lebedev derives his wealth from his father Alexander, a billionaire oligarch, who was previously described as a Putin critic but is thought to retain close ties to the Kremlin.
In a statement last week, Lebedev said: “I am not a security risk to this country, which I love. My father, a long time ago, was a foreign intelligence agent of the KGB, but I am not some agent of Russia.
“The editorial coverage in The Independent and the Evening Standard (of which I am also a shareholder) of Russia and its activities, over the time of my involvement in those titles, makes that clear.”
He added: “I may have a Russian name, but that makes me no less a committed or proud British citizen than anyone else in this country of ours. Being Russian does not automatically make one an enemy of the state, and it is crucial we do not descend into Russophobia, like any other phobia, bigotry or discrimination.
“Like you, I pray for president Putin to end the war in Ukraine.”