While it's true that only a handful of the 28 member countries now spend 2 percent or more of their GDP on defense, a 2014 agreement gave all of them a decade to get to the 2 percent level.
Trump, who later arrived at NATO's new billion-dollar headquarters in his presidential limousine, appeared to substantially overstate German reliance on Russian energy and to imply the German government was funding the pipeline, which Berlin says is a commercial venture.
Asked about Mr Trump's suggestion, NATO Secretary-General Jens Stoltenberg said he would focus on what has been agreed to.
After Putin complained that White House officials tried to stop their phone call from happening, Trump told Putin, "Those are stupid people; you shouldn't listen to them", according to NYT via The Hill. "And I think we have to talk to Germany about it".
The president's critics have accused him of ignoring USA barriers to foreign products, and of seeking a tariff-fueled trade war with the Europeans (and the Chinese) that will undermine economies worldwide.
Bloomberg omitted the part where Radev said that Trump spoke first and added a claim from the Bulgarian leader that the US president left the meeting immediately after his own remarks.
The NATO alliance consists of 29 countries from North America and Europe, including the US and Germany, which was originally set up in 1949 to thwart Soviet aggression in Western Europe.
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During the day England fans were planning the best and least expensive way to get hold of a ticket for the final. But the sense that history was in the making brought them here to Moscow in force for this semi-final.
"It certainly doesn't seem to make sense that they pay billions of dollars to Russia, and now we have to defend them against Russia", Trump said.
Trump's surprise demand came after he clashed with Chancellor Angela Merkel, calling Germany a "captive" of Russian Federation because of its gas links and singling out Berlin for failing to pay its way.
"They will be getting between 60 and 70 percent of their energy from Russian Federation and a new pipeline". She's your leading economic partner here in Europe.
The pair later met for a one-on-one meeting and while Trump insisted they had a "very very good relationship", their frosty body language suggested otherwise.
The unexpected demand from Trump during a closed-door meeting of heads of state laid down a new, virtually unachievable marker for a peacetime military spending in an alliance already struggling to meet current defense spending commitments. "We'll see how that goes".
Despite his continued criticism of the transAtlantic pact, Trump on Wednesday signed the 23-page North Atlantic Treaty Organisation declaration, along with his 28 other allies, which reaffirmed the two percent goal to be reached by 2014.
Throughout the day, leaders were peppered with questions about Trump's behavior and whether or not they agreed with his position on Germany.
Mr Trump is due to hold his first summit with Vladimir Putin, in Helsinki, on 16 July.