Francois Hollande says his personal life must remain private

French President Francois Hollande, under fire over an alleged affair with an actress, refused on Tuesday to discuss his personal life but said he would clarify the status of France's first lady before a visit to the United States next month.

His official partner, Valerie Trierweiler, has been in hospital since last Friday after a celebrity magazine published photos of what it said was Hollande in a motorcylist's helmet visiting actress Julie Gayet for nocturnal trysts.

"Everyone in their personal life can face trials. That's our case. These are painful moments. But I have one principle, and that is that personal life should be treated privately, respecting each person's intimacy," Hollande told a news conference.

"This is neither the place nor the moment to (discuss) that. If I do not respond to any question on that topic today, I will do so before (the U.S. visit)," Hollande said.