Or so the story goes when told by the Prime Minister.
But the Kremlin has dismissed the much-told tale, telling Mr Cameron that the 'agents' were in fact dodgy salesmen.
Moscow's secret services delivered a further blow to the Old Etonian by claiming that he had simply been the target of a gay pick-up.
Mr Cameron first told the story in 2006 on the BBC Radio 4 programme Desert Island Discs.
At the time he said: "I travelled on the Trans-Siberian railway... and then met a great friend in Moscow. We went down to the Black Sea and were on the beach in Yalta.
"These two Russians who spoke perfect English sort of turned up on the beach, which was mainly reserved for foreign tourists, and took us out to dinner, and interrogated us in a very friendly way about life in England and politics."
Russian newspaper Komsomolskaya Pravda yesterday scotched the idea.
The newspaper quoted Gennady Sokolov, a Russian author and intelligence historian, who said secret service sources had told him that there had been no bid to recruit Mr Cameron.
He said: "If the KGB had a task to work with a 19-year-old unknown young man Cameron, there would have remained certain paperwork on this matter.
"We have cautiously asked well-informed people if there is a file on Cameron in KGB archives. We got a definite reply that there is no such file in the archives, and there was no such file earlier. The KGB was not working on Cameron."
He even claimed to have tracked down the two men and they were in fact black market salesmen attempting to buy banned Western goods from tourists.
He said: "The pair planned to buy some foreign stuff like jeans to resell them later and, after all, to make friends with two nice looking British guys - there was also a gay motive."
Mr Cameron may be somewhat naive, but others have already presumed the Russian gentlemen may have had other motives.
Thanks to comrade Darren x.