Ukrainian President Petro Poroshenko, left, German Chancellor Angela Merkel and U.S. Vice President Joe Biden, background right, arrive for a meeting in Munich, Germany on Saturday. Matthias Schrader/AP hide caption

itoggle caption Matthias Schrader/AP

German Chancellor Angela Merkel, left, and Mayor of Berlin Klaus Wowereit, 3rd from left, place candles to commemorate the victims of the Wall at the Berlin Wall memorial site at Bernauer Strasse in Berlin, Germany, on Sunday. Markus Schreiber/AP hide caption

itoggle caption Markus Schreiber/AP

News of U.S. surveillance in Europe has met with distrust and anger; officials are heading to Washington to discuss matters next week. Here, members of an artists' group paint a mural called "Surveillance of the Fittest" on a wall in Cologne, Germany, on Thursday. Frank Augstein/AP hide caption

itoggle caption Frank Augstein/AP