"Germany remains one of America's closest and strongest allies - an indispensable partner not only for our own security and those of our NATO allies, but also for the security, the prosperity and the dignity of people across the whole world," he told Bild in an interview published on Saturday.
"With Chancellor Merkel, Germany has raised the stakes and plays an even bigger role on the international stage," he said, with her work to tackle terrorism, reaching a nuclear deal with Iran and
On Sunday, Obama attended the Hannover Messe trade show, which showcases industrial technology. This year's partner country is the U.S., with over 250 U.S. companies participating in the show. Obama is the first sitting U.S. president to visit the event.
Obama's trip to Germany has not gone without a hitch so far, with thousands of protesters gathering in Hannover on Saturday to protest a planned but unpopular free trade agreement between the U.S. and EU, known as the Transatlantic Trade and Investment Partnership (TTIP). Critics of TTIP fear it threaten public services, the environment and consumers.
Despite concerns over the secretive nature of trade talks, both Obama and Merkel said on Sunday that they hoped to have an agreement over the trade deal by the end of the year.
On Monday afternoon, Obama is expected to meet with Merkel, French President Francois Hollande, Italian Prime Minister Matteo Renzi and U.K. Prime Minister David Cameron. They are expectred to discuss security and humanitarian concerns over Libya and fragile Syrian peace talks.
Obama's trip to Germany comes after a brief stay in London last week during which he made a call for the U.K. to remain within the European Union (EU) ahead of a referendum on the subject on June 23. His comments during the visit made for uncomfortable listening at times with Obama saying that if the U.K. left, it should not expect any preferential treatment from its long-term ally.
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