Obama tests virtual reality goggles at the Hannover Messe on April 25.
Obama tests virtual reality goggles at the Hannover Messe on April 25.
Christian Charisius/dpa via AP
From left, British Prime Minister David Cameron, Italian Prime Minister Matteo Renzi, U.S. President Barack Obama, German Chancellor Angela Merkel and French President Francois Hollande sit together at Herrenhausen Palace in Hanover, Germany, on Monday, April 25. Germany was the third stop on Obama's recent trip, which also included the United Kingdom and Saudi Arabia.
From left, British Prime Minister David Cameron, Italian Prime Minister Matteo Renzi, U.S. President Barack Obama, German Chancellor Angela Merkel and French President Francois Hollande sit together at Herrenhausen Palace in Hanover, Germany, on Monday, April 25. Germany was the third stop on Obama's recent trip, which also included the United Kingdom and Saudi Arabia.
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Obama and Merkel look at a robotic device April 25 as they tour the Hannover Messe, the world's largest trade fair for industrial technology.
Obama and Merkel look at a robotic device April 25 as they tour the Hannover Messe, the world's largest trade fair for industrial technology.
Michael Sohn/AP
Obama and Merkel look at a gripping device at the Hannover Messe on April 25.
Obama and Merkel look at a gripping device at the Hannover Messe on April 25.
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From left, U.S. Secretary of Commerce Penny Pritzker, Obama and Merkel attend the opening ceremony of the Hannover Messe on Sunday, April 24.
From left, U.S. Secretary of Commerce Penny Pritzker, Obama and Merkel attend the opening ceremony of the Hannover Messe on Sunday, April 24.
RONNY HARTMANN/AFP/Getty Images
Obama and Merkel hold a news conference after bilateral talks at Herrenhausen Palace on April 24.
Obama and Merkel hold a news conference after bilateral talks at Herrenhausen Palace on April 24.
Markus Schreiber/AP
Merkel welcomes Obama at Herrenhausen Palace on April 24.
Merkel welcomes Obama at Herrenhausen Palace on April 24.
Markus Schreiber/AP
Obama speaks at a news conference in London on Saturday, April 23.
Obama speaks at a news conference in London on Saturday, April 23.
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British Prime Minister David Cameron and Obama play golf at the Grove Golf Club on April 23.
British Prime Minister David Cameron and Obama play golf at the Grove Golf Club on April 23.
Andrew Parsons/Cal Sport Media/Zuma Press
Obama takes a brief tour of the Globe Theatre in London with Patrick Spottiswoode, director of Globe Education, marking the 400th anniversary of the death of William Shakespeare on April 23.
Obama takes a brief tour of the Globe Theatre in London with Patrick Spottiswoode, director of Globe Education, marking the 400th anniversary of the death of William Shakespeare on April 23.
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Obama, Prince William and first lady Michelle Obama talk with Prince George at Kensington Palace on Friday, April 22.
Obama, Prince William and first lady Michelle Obama talk with Prince George at Kensington Palace on Friday, April 22.
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Queen Elizabeth II and her husband, Prince Philip, greet Obama outside Windsor Castle on Friday, April 22.
Queen Elizabeth II and her husband, Prince Philip, greet Obama outside Windsor Castle on Friday, April 22.
JIM WATSON/AFP/Getty Images
A motorcade drives the Obamas to Windsor Castle for lunch with Queen Elizabeth II on April 22.
A motorcade drives the Obamas to Windsor Castle for lunch with Queen Elizabeth II on April 22.
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Obama arrives at Downing Street to meet with Cameron on April 22. <a href="http://www.cnn.com/2016/04/22/politics/barack-obama-david-cameron-press-conference/index.html">The American leader is urging British voters to reject the chance to leave the European Union</a> in a national referendum scheduled for June.
Obama arrives at Downing Street to meet with Cameron on April 22. The American leader is urging British voters to reject the chance to leave the European Union in a national referendum scheduled for June.
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Before Britain, Obama met with Oman's Deputy Prime Minister Sayyid Fahad Mahmoud Al Said, left, and Saudi King Salman at the Gulf Cooperation Council summit, which took place Thursday, April 21, in Riyadh, Saudi Arabia. Obama spoke with Gulf leaders about regional conflicts, the role of Iran and the fight against ISIS.
Before Britain, Obama met with Oman's Deputy Prime Minister Sayyid Fahad Mahmoud Al Said, left, and Saudi King Salman at the Gulf Cooperation Council summit, which took place Thursday, April 21, in Riyadh, Saudi Arabia. Obama spoke with Gulf leaders about regional conflicts, the role of Iran and the fight against ISIS.
Carolyn Kaster/AP
Obama confers with other leaders at the Gulf Cooperation Council summit on April 21.
Obama confers with other leaders at the Gulf Cooperation Council summit on April 21.
Carolyn Kaster/AP
The United States and Saudi Arabia have been divided over a slew of issues, including the approach to the wars in Syria and Yemen, the Iranian nuclear deal and the influence Tehran wields in Iraq. Here, Obama appears with Saudi King Salman, Bahrain's King Hamad bin Isa Al Khalifa and Abu Dhabi Crown Prince Mohamed bin Zayed Al Nahyan during the Riyadh summit on April 21.
The United States and Saudi Arabia have been divided over a slew of issues, including the approach to the wars in Syria and Yemen, the Iranian nuclear deal and the influence Tehran wields in Iraq. Here, Obama appears with Saudi King Salman, Bahrain's King Hamad bin Isa Al Khalifa and Abu Dhabi Crown Prince Mohamed bin Zayed Al Nahyan during the Riyadh summit on April 21.
JIM WATSON/AFP/Getty Images
Obama and Saudi King Salman meet at Erga Palace in Riyadh on Wednesday, April 20. The White House moved to tamp down suggestions that ties with Saudi Arabia are fraying, with administration officials saying the two leaders "really cleared the air" in their meeting.
Obama and Saudi King Salman meet at Erga Palace in Riyadh on Wednesday, April 20. The White House moved to tamp down suggestions that ties with Saudi Arabia are fraying, with administration officials saying the two leaders "really cleared the air" in their meeting.
Carolyn Kaster/AP
Obama arrives on Air Force One at King Khalid International Airport in Riyadh on April 20. Saudi King Salman did not greet the President on his arrival. The perceived slight was seen as one more sign that the U.S.-Saudi relationship is encountering friction.
Obama arrives on Air Force One at King Khalid International Airport in Riyadh on April 20. Saudi King Salman did not greet the President on his arrival. The perceived slight was seen as one more sign that the U.S.-Saudi relationship is encountering friction.
Carolyn Kaster/AP
Obama tests virtual reality goggles at the Hannover Messe on April 25.
Obama tests virtual reality goggles at the Hannover Messe on April 25.
Christian Charisius/dpa via AP
Obama tests virtual reality goggles at the Hannover Messe on April 25.
Obama tests virtual reality goggles at the Hannover Messe on April 25.
Christian Charisius/dpa via AP