"What we would like to recall is the principle to which we all subscribe on the international level, which is non-interference in internal affairs," Republic of Congo President Sassou Nguesso told journalists on a trip to France.
Two Parisian prosecutors have been investigating the conditions under which numerous luxury assets were acquired in France by Sassou Nguesso, as well as Gabon's late president Omar Bongo and Equatorial Guinea leader Teodoro Obiang Nguema Mbasogo.
These are believed to include French Riviera and Parisian residences and fleets of cars.
The probe was triggered by a suit filed in 2008 by non-governmental organisations Sherpa and Transparency International France, calling for an investigation in the matter.
Sassou Nguesso said on Monday that the principle of non-interference should be "respected so that French justice does not feel it has the right to deal with matters that relate to the internal affairs of other states".
Asked by a journalist whether he had lost any sleep over the affair, the leader of the oil-rich central African country -- who held more than an hour of talks with Hollande -- replied, "Certainly not!"
The lawyer for Transparency International, meanwhile, blasted Sassou Nguesso for embodying "a caricature of kleptocracy, of a rich head of state that leads a poor country."
"It's not about non-interference but about putting into practice French and international law," William Bourdon said.