German Chancellor Angela Merkel stands with U.S. President Barack Obama and Berlin Mayor Klaus Wowereit (R) behind a bullet proof glass at the Brandenburg Gate in Berlin, June 19, 2013. U.S. President Barack Obama will unveil plans for a sharp reduction in nuclear warheads in a landmark speech at the Brandenburg Gate on Wednesday that comes 50 years after John F. Kennedy declared "Ich bin ein Berliner" in a defiant Cold War address. REUTERS/Fabrizio Bensch (GERMANY - Tags: POLITICS)