Boris Johnson has told MPs he met Russian oligarch and ex-KGB officer Alexander Lebedev without officials present.
"I have certainly met him without officials," he said. "I met him on a very few occasions."
And when asked if he met the Russian billionaire and former Evening Standard owner while foreign secretary in Italy in 2018, he said he had.
Mr Johnson made Mr Lebedev's son Evgeny a member of the House of Lords.
Controversy surrounds that appointment, since it was alleged - first in a Tortoise Media podcast and then in the Sunday Times - that the peerage was granted despite a warning from the security services that it posed a national security risk.
The Soviet KGB was the main Cold War rival of Western security services, and President Vladimir Putin was a KGB officer too. Many of Mr Putin's closest aides were KGB comrades.
Mr Johnson was answering a question from Labour's Dame Diana Johnson on the Commons Liaison Committee.
"I certainly have met the gentleman in question, who used to be the proprietor of the London Evening Standard when I was mayor of London," the prime minister said.
"On the occasion you are mentioning, if that was when I was foreign secretary, then yes."
Lord Lebedev, current owner of the Evening Standard, has denied posing a "security risk" to the UK.
The Sunday Times said the security services' assessment was withdrawn after Mr Johnson - a long-time friend of Lord Lebedev - personally intervened.