Ivory Coast’s Prime Minister, Patrick Achi, is in hospital in the French capital, Paris, sources close to his office say.
He is said to be having medical tests.
Mr Achi was appointed prime minister in March following the death of his predecessor Hamed Bakayoko, who had been receiving treatment for cancer in Germany.
Mr Bakayoko, himself, was appointed following the sudden death of his predecessor Amadou Gon Coulibaly last year.
Reuters news agency says that Mr Achi went to France last week for health reasons but then returned to Ivory Coast to take part in talks about electricity problems. He then flew back to Paris on Tuesday.
The Ivorian government has not commented