Story highlights The President has offered varying stances on NATO during his campaign and presidency

Trump has questioned the alliance's relevance, but since taking office he's avoid the harsh rhetoric

(CNN) President Donald Trump vowed stout support for NATO on Monday, even as he insisted again that member countries scale up their defense spending on the alliance.

Trump has offered varying stances on NATO during his campaign and presidency, calling the membership obsolete and ill-prepared to confront modern-day threats. His remarks Monday signaled he would maintain US backing for the partnership while continuing to press other countries to meet its budget requirements.

"We strongly support NATO," Trump said at the headquarters of US Central Command in Florida. "We only ask that all of the NATO members make their full and proper financial contributions to the NATO alliance, which many of them have not been doing. Many of them have not been even close. And they have to do that."

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NATO expects its members to commit to spending 2% of their gross domestic products on defense. Only five of the 28 countries that belong to NATO have met that goal.

Trump has long criticized the shortfalls, suggesting the US was subsidizing other nations' security at the expense of its own. But since taking office, he's avoided the harsh rhetoric he used on the campaign trail questioning the alliance's relevance.

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