In July, then-Republican candidate Donald Trump unnerved many European leaders when he said, if elected president of the United States, he would be reluctant to come to the aid of NATO allies unless they paid their fair share of the costs for the long-standing alliance.
"If they fulfill their obligations to us, the answer is yes," Trump told the New York Times.
On Monday, President Barack Obama told reporters during a press conference that during his meeting with him, President-elect Trump assured him that he was committed to NATO.
Trump complained to the Washington Post's editorial board back in March that the United States was footing the majority of the bill for NATO.
"We certainly can't afford to do this anymore," Trump said. "NATO is costing us a fortune, and yes, we're protecting Europe with NATO, but we're spending a lot of money."
It's certainly not a new complaint. U.S. military and diplomatic leaders have urged NATO allies for years to pay more to keep the alliance strong and intact. The Pentagon wants all member nations to pay at least 2% of their gross domestic product on the NATO budget.
"Every ally spending less than 2% of their GDP needs to dig deeper and make a concrete commitment to do more. And all you have to do is look at a map in order to understand why – Ukraine, Iraq, Syria – all threats to peace and to security, and they surround the region," Secretary of State John Kerry said at NATO headquarters in Brussels in 2014.
The Trump transition team did not immediately respond to a request for comment from Mic.