Donald Trump has backed down over threats to pull the US out of Nato after other leaders agreed to increase defence spending "like they never have before".
The US president described himself as a "very stable genius" for securing agreements for extra cash after years of the burden falling on America.
Mr Trump said he told counterparts on Wednesday that he was "extremely unhappy" with the lack of progress being made towards meeting the alliance target of spending 2% of GDP on defence.
But he said that since last year around an additional 33 billion dollars, not including the United States, had been raised and it was now "unnecessary" to withdraw from the organisation.
"The United States' commitment to Nato remains very strong," he said.
Mr Trump said Nato was "probably the greatest" but the US had been paying between 70-90% towards it.
Speaking in Brussels, he told reporters: "Yesterday, I let them know I was extremely unhappy with what was happening and they have substantially upped their commitment."
Nato was now "much stronger than it was two days ago", he said.
"I believe in Nato," he added.
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