NATO Secretary General Jaap de Hoop Scheffer (1st L), U.S. President Barack Obama (2nd L), French President Nicolas Sarkozy (R) and German Chancellor Angela Merkel (rear) reach France after crossing German-French border bridge, Passerelle Bridge, which connected German city Kehl and French city Strasbourg, on April 4, 2009. Leaders of NATO member states held a symbolic ceremony on the French-German border on Saturday to celebrate the 60th anniversary of the military alliance and the return of France as a full member. [Wu Wei/Xinhua]