Information Minister Khieu Kanharith posted on his Facebook page that Ranariddh died at 9.40am in France, without mentioning the cause of death.
The prince, who had been involved in two traffic accidents in Cambodia, had undergone six surgeries, which resulted in deterioration of his health, according to an assistant to the prince.
File photo shows Cambodian Prince Norodom Ranariddh (left) alongside Prime Minister Hun Sen (right) in July 2004 in Phnom Penh. (Kyodo)
The prince was the second son of the late King Norodom Sihanouk and a half-brother of the current king, Norodom Sihamoni.
Following general elections organized by the UN in 1993 and won by Ranariddh’s royalist party, FUNCINPEC, he was first prime minister and Hun Sen, the current prime minister, second prime minister. The prince later became president of the National Assembly.
Ranariddh was ousted in a 1997 coup by Hun Sen.
Sources inside the Cambodian royal palace said Ranariddh’s body would be sent back to the country for an official funeral.