French First Lady Valerie Trierweiler is going on Sunday to India in support of a charity effort, an aide said, after a week-long stay in hospital following revelations that her partner Francois Hollande is having an affair with an actress.

Trierweiler "is going to Mumbai," said the aide, adding that the two-day trip was organised by relief organisation Action Against Hunger.

The aid group had invited Trierweiler in her official capacity, but following revelations of Hollande's affair with 41-year-old French actress Julie Gayet, it is unclear if she is travelling as first lady.

Trierweiler remains holed up in a presidential residence in Versailles outside Paris after leaving hospital last Saturday where she was treated for a bout of "tiredness" brought on by the press reports.

Yesterday, Frederique Giffard, a lawyer for 48-year-old Trierweiler, said her client wanted a "clarification" to the tangled situation.

But Trierweiler, in a furious reaction soon after, said Giffard was speaking without her permission and added that she was no longer her lawyer.

Hollande had promised in a mid-January news conference that he would publicly define what relationship he and Trierweiler are in before going on a February 11 state visit to Washington.

The 59-year-old leader has so far made no official comment on whether France still has a first lady.