Trump aims to reassure allies about US support, but asks them to pay up more

President Donald Trump aimed to reassure American allies about military support Monday, but again said he expects them to contribute more to defense.

Speaking after a meeting with the United States Central Command, Trump affirmed support for the North Atlantic Treaty Organization, the military alliance he criticized on the campaign trail. While he signaled his backing for the 28-member group, Trump urged allies to "pay their fair share" as part of the alliance.

"They're very unfair to us. We strongly support NATO, we only ask that all NATO members make their full and proper financial contribution to the NATO alliance, which many of them have not been doing," Trump told military officials at MacDill Air Force Base in Florida.

As a candidate, Trump sparked concerns in Europe for suggesting that he could set conditions for defending members who were under attack. He questioned NATO's continued relevance.

Since, though, he has pulled back his criticism of the alliance while maintaining that he wants allies to contribute more to defense spending. Trump spoke to NATO's secretary-general on Sunday, discussing "how to encourage NATO allies to meet their defense spending commitments" and agreeing to go to a meeting of NATO leaders in Europe later this year, according to the White House.

Trump's criticism of the alliance appears to relate to a guideline that member countries should spend 2 percent of their gross domestic product on defense, a standard that most do not meet. NATO says only five of 28 members were estimated to hit that mark in 2016.

After Trump met with British Prime Minister Theresa May last month, May said the pair is "100 percent behind NATO." May said she "agreed to continue my efforts to persuade my fellow European leaders to deliver on their commitment to spend 2 percent of GDP on defense, so that the burden is more fairly shared."

Trump's predecessor President Barack Obama also expressed concerns about NATO members contributing enough.

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