US President Barack Obama, center, poses for a group photograph Sunday, November 20, at the summit of the Asia-Pacific Economic Cooperation. The summit was held in Lima, Peru. Joining Obama in this photo, from left, are Thai Deputy Prime Minister Prajin Juntong, Japanese Prime Minister Shinzo Abe, South Korean Prime Minister Hwang Kyo-ahn and Vietnamese President Tran Dai Quang. Obama is on his last international trip as president. He made earlier stops in Greece and Germany.
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Obama addresses a town-hall meeting in Lima for the Young Leaders of the Americas Initiative.
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Obama takes a question during the town-hall meeting, which took place on Saturday, November 19.
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Cyntia Paytan greets Obama after introducing him at the town-hall meeting.
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Obama and other leaders wait for a meeting November 19 during the summit of the Asia-Pacific Economic Cooperation.
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Obama confers with Peruvian President Pedro Pablo Kuczynski during the summit on November 19.
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Mercedes Araoz, Peru's second vice president, joins Obama on the tarmac after his arrival at an airport near Lima on Friday, November 18.
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On his way to Peru, Obama boards Air Force One during a refueling stop in the Azores on November 18.
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Obama walks across the tarmac during the refueling stop in the Azores.
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Obama meets with, from left, British Prime Minister Theresa May, Spanish Prime Minister Mariano Rajoy, Italian Prime Minister Matteo Renzi, French President François Hollande and German Chancellor Angela Merkel at the German Chancellery in Berlin on November 18.
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Merkel welcomes Obama before a meeting in Berlin on Thursday, November 17.
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Obama walks past the Brandenburg Gate after visiting the US Embassy in Berlin on November 17.
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Obama is greeted by a guard of honor after flying into Berlin on Wednesday, November 16.
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Obama waves to the crowd after delivering a speech at the Stavros Niarchos Foundation in Athens, Greece, on November 16.
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Obama tours the Acropolis in Athens on November 16.
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Obama meets with Greek President Prokopis Pavlopoulos at the presidential mansion in Athens on Tuesday, November 15. Obama called Greece a "reliable ally" in its commitment to NATO, even as the country faces tremendous strain from its debt crisis.
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Obama and Greek Prime Minister Alexis Tsipras field questions at a joint news conference in Athens on November 15.
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Tsipras welcomes Obama before formal talks in Athens on November 15.
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Obama reviews a presidential honor guard during an official welcoming ceremony in Athens on November 15.
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Obama arrives at Athens International Airport on November 15.
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Greek presidential guards parade outside the presidential mansion in Athens on November 15.
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Air Force One touches down at the Athens airport on November 15. Obama was the first sitting US president to visit Greece since Bill Clinton in 1999.