Trump calls Canadian leader 'two-faced' as row erupts over secretly filmed video

As NATO leaders professed unity at a summit near London, a spat rippled under the surface after several were caught in an unguarded exchange on camera apparently gossiping about US President Donald Trump's behaviour.

Trump branded Canadian Prime Minister Justin Trudeau "two-faced" after the remarks captured during a reception in London at Buckingham Palace.

Trudeau was seen standing in a huddle with French President Emmanuel Macron, British Prime Minister Boris Johnson, Dutch Prime Minister Mark Rutte and Princess Anne at the Tuesday evening (local time) event.

Canadian Prime Minister Justin Trudeau in animated conversation with French President Emmanuel Macron, Britain's Prime Minister Boris Johnson and Nato Secretary General Jens Stoltenberg. Source: AAP

After Johnson asked Macron, "is that why you were late?" Trudeau could be heard saying "He was late because he takes a 40-minute press conference off the top." 

That appeared to be a reference to Trump's long and unscheduled question-and-answer session with journalists earlier on Tuesday.

Trudeau also said: "You just watched his team's jaws drop to the floor."

Trump wasn't mentioned by name during the exchange.

Footage of the palace reception was recorded by a pool camera. The clip was posted online by Canadian broadcaster CBC and has been viewed more than five million times.

Trump said on Wednesday that Trudeau was likely upset that the US president had broached the fact that Canada falls short of the NATO target of spending two per cent of its gross domestic product on defence.

"Well, he's two-faced," Trump told reporters. "And honestly, with Trudeau he's a nice guy, I find him to be a very nice guy but you know the truth is that I called him out on the fact that he's not paying two per cent and I guess he's not very happy about it."

Trudeau's office had no immediate comment. Trudeau spoke briefly to Trump as NATO leaders gathered for a summit on Wednesday in Watford, outside London, and the two men shook hands.

Leaders of the 29 NATO states are marking the 70th anniversary of the military alliance, and trying to patch up differences over defence spending, the alliance's strategic direction and member nation Turkey's military action in northern Syria.

Following Mr Trudeau’s private comments about Trump’s expansive press conferences, the US president left the NATO summit early.

President Donald Trump at the NATO summit, where four other world leaders were captured. Source: AAP

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