Washington, Apr 9: Rocker Lenny Kravitz has reportedly been approached by French First Lady Carla Bruni to work on her new album.

The 44-year-old singer-songwriter revealed that he had received a letter of praise from President Nicolas Sarkozy.

The letter is said to have paved the way for collaboration between him and the model-turned-singer Bruni, who Kravitz claims to know from "back in the day."