Lithuania's President Valdas Adamkus, Estonian Prime Minister Andrus Ansip, Belgium's Prime Minister Herman Van Rompuy, Latvia's President Valdis Zatlers and Britain's Prime Minister Gordon Brown (L-R) walk on the Two Banks Bridge on the Rhine river in Kehl, April 4, 2009. The North Atlantic Treaty Organisation (NATO) military alliance is celebrating its 60th anniversary this week at a summit co-hosted by Germany and France. REUTERS/Hannibal Hanschke (GERMANY)