The head of police, Frederic Pechenard, and the head of the DCRI domestic intelligence agency, Bernard Squarcini, "have been summoned" by the judge investigating a suit by Le Monde newspaper.
They will likely be interviewed in mid-October.
The source was not able to say whether the men would be questioned as witnesses or potential suspects, but the interviews could result in charges being brought.
Police allegedly obtained journalists' mobile telephone logs in 2010 in order to identify the source in a complex illegal political financing scandal linked to L'Oreal heiress and billionaire Liliane Bettencourt.
The scandal began as a dispute between the heiress and her daughter, but soon evolved into allegations that Bettencourt had been handing bundles of cash to politicians, including Sarkozy's 2007 presidential campaign manager.
The manager, Eric Woerth, lost his job as employment minister last year as a result of the allegations.
Sarkozy, who has yet to announce his candidacy in the next presidential election that is barely seven months away, has been mired in corruption and illegal campaign financing allegations in recent weeks.
Two of his aides were this week charged in connection with alleged illegal financing connected to a submarine sale to Pakistan in the 1990s.