France's outgoing President Nicolas Sarkozy's wife Carla Bruni (L), welcomes Francois Hollande's companion Valerie Trierweiler at the Elysee Palace in Paris, France, May 15, 2012. The power handover ceremony between Sarkozy and Francois Hollande was held here on Tuesday morning, when Hollande was officially sworn in as France's president. [Xinhua]