President Obama's Europe Trip

U.S. President Barack Obama walks with Italian Prime Minister Matteo Renzi, Canadian Prime Minister Stephen Harper, German Chancellor Angela Merkel, British Prime Minister David Cameron, French President Francois Hollande, European Commission President Jose Manuel Barroso and Japanese Prime Minister Shinzo Abe after a G7 group photo in Brussels, June 5, 2014.

U.S. President Barack Obama laughs as he looks at British Prime Minister David Cameron during a G7 session in Brussels, June 5, 2014.

U.S. President Barack Obama meets with Belgian King Philippe and Belgian Prime Minister Elio Di Rupo at the Royal Palace of Brussels, June 4, 2014.

U.S. President Barack Obama and Polish President Bronislaw Komorowski show the peace sign at a Freedom Day event at Royal Square in Warsaw, June 4, 2014.

U.S. President Barack Obama speaks during a ceremony marking the "Freedom Day" anniversary in Warsaw's Castle Square, June 4, 2014.

U.S. President Barack Obama speaks during a ceremony marking the Freedom Day anniversary in Castle Square in Warsaw, June 4, 2014.

U.S. President Barack Obama shakes hands with Ukraine's President-elect Petro Poroshenko during their meeting in Warsaw, June 4, 2014.

U.S. President Barack Obama and Polish President Bronislaw Komorowski walk away after a group photo with Central and Eastern European Leaders in Warsaw, June 3, 2014.

U.S. President Barack Obama is welcomed by Polish Prime Minister Donald Tusk in Warsaw, June 3, 2014.

U.S. President Barack Obama and Poland's President Bronislaw Komorowski walk to make statements after meeting U.S. and Polish troops at an event featuring F-16 fighter jets in Warsaw, June 3, 2014.