In a hugely symbolic gesture the leaders of NATO have walked across a footbridge from Germany to France to attend their summit, to emphasise the renewed cooperation within the alliance.Led by German Chancellor Angela Merkel, they were greeted halfway by French President Nicolas Sarkozy, who has recently been given the green light to bring his country back into the alliance’s military command, after it was withdrawn by General Charles de Gaulle in 1966. This was the second day of NATO’s 60th anniversary summit, which began in Baden Baden and Kehl in Germany yesterday. On the French side of the bridge, known as the Passerelle des Deux Rives, the 28 leaders paused for a short ceremony in honour of NATO’s military personnel, particularly those who have lost their lives or been injured in conflicts the organisation has been involved in. This was followed by a minute’s silence. Strasbourg, a picturesque city in northeastern France, has been under lockdown for days due to security concerns. Some 9000 riot police and security officials are in the city and there have been severe clashes with protestors. Founded on April 4 1949, NATO originally had eleven members. The alliance has now expanded to 28, following the ratification on Wednesday of the membership of Croatia and Albania. Its future expansion, particularly to the east, remains a politically sensitive issue.