NATO is the "bulwark of international peace and security" but its European members "must pay what they owe," US President Donald Trump said on Wednesday alongside the political head of the military alliance.
Reversing some of his campaign rhetoric, Trump told a news conference that NATO "is no longer obsolete" and hailed its role in the fight "against terrorism."
But he renewed his argument that NATO's member states need to dedicate two percent of their gross domestic product to military expenditure.
"In facing our common challenges, we must also ensure that NATO members meet their financial obligations and pay what they owe," he said.