A nude photo of France's first lady Carla Bruni-Sarkozy is to be auctioned off at a Christie's sale in New York City.

The photo from the collection of Gert Elfering, estimated at $3000-$4000 will go on sale on 10 April 10.

The image was taken by photographer Michel Comte in 1993, when Bruni-Sarkozy was one of the world's most coveted models.

Comte says he has more explicit pictures but that he will not sell them, according to artknowledgenews.com.

In an interview published in Le Matin, Comte, says that he does not know how the picture got to Christie's where it will be auctioned, and says it must have been a gift to someone.

Comte worked with Carla for about 10 years. He says that she is "naked in this picture but at the same time shows her masculine side".

Bruni signed with City Models at age 19. In the 1990's she was pulling in about $7-million a year modelling and she dated a list of famous men including Eric Clapton, Mick Jagger and Donald Trump.