A nude portrait of French President Nicolas Sarkozy's wife Carla Bruni is seen here in this undated handout photo from Christie's auction house. A nude portrait of French President Nicolas Sarkozy's wife Carla Bruni will go under the hammer in New York next month, according to auctioneers Christie's. It was taken in 1993, when Bruni was one of the world's top fashion models. It is expected to fetch $3,000 to $4,000 when it is sold in New York on April 10, according to the Christie's web site. [Agencies]