French first lady Carla Bruni-Sarkozy sang at a concert in New York to commemorate Nelson Mandela's 91st birthday -- the first time she has sung in public since marrying French President Nicolas Sarkozy.
Dressed in black trouser suit, Bruni-Sarkozy strummed guitar alongside former Eurythmics musician Dave Stewart as they performed a duet on Saturday night, singing a slower version of Bob Dylan's "Blowin' in the Wind" while the French president smiled and clapped sitting in the audience.
"It's not very good for dancing but very good for dreaming," the 41-year-old former model said before launching into her French hit "Quelqu'un m'a dit" ("Someone told me") that left the crowd whooping.
The concert held at New York's Radio City Music Hall also featured such prominent artists as Aretha Franklin, Queen Latifah and disco queen Gloria Gaynor as well as African artists, including Baaba Maal.
Besides Franklin, some of the biggest applause came when Cyndi Lauper paired up with American rapper Lil' Kim to sing "Time After Time", while Alicia Keys and African artist Angelique Kidjo swirled their hips singing "Afrika."
Stevie Wonder was joined on stage for the finale by all the concert's performers and actors including Morgan Freeman, Forest Whitaker and Susan Sarandon singing Wonder's hit "Happy Birthday" while the Soweto Gospel choir sang throughout the three-hour concert.
Mandela, who is very frail, was not at the "Mandela Day" concert as he has been advised he should no longer travel internationally but he delivered a video message.
"Our struggle for freedom and justice was a collective effort. Mandela Day is no different," he said. "It is our hope that people will dedicate their time and effort to improve the conditions within their own community."
President Barack Obama also delivered a message via video, saying Mandela's life taught people to have courage.
"From New York to Cape Town, people are celebrating this extraordinary man," Obama said. "The story of his life can be summed up in Nelson Mandela's own words, 'It always seems impossible until it's done.'"
More pictures of Carla Bruni's performance