Trump vents anger on North Atlantic Treaty Organisation allies, European Union and Canada's Trudeau

White House economic adviser Larry Kudlow and trade adviser Peter Navarro drove the message home in an extraordinary assault on a close USA ally and neighbour.

Tusk was referencing a comment made by Trump aide Peter Navarro, who shocked even the US President's Republican colleagues when he called Trudeau a backstabber - over the issue of trade tariffs - and verbally consigned him to "hell" after a G7 meet in Canada over the weekend.

The coordinated attack against Trudeau from the USA officials, not to mention Trump's tweets calling Trudeau "weak" and dishonest, has led former US ambassador to Canada Bruce Heyman to conclude the White House is trying to make Canada the scapegoat for troubled NAFTA negotiations. "That's what weak, dishonest Justin Trudeau did, and that comes right from Air Force One".

At an event hosted by the Journal, Navarro said he had made a mistake, according to the newspaper.

Foreign Affairs Minister Chrystia Freeland said Sunday that "Canada does not believe that ad hominem attacks are a particularly appropriate or useful way to conduct our relations with other countries".

"Very childish and unprofessional behaviour", Gorka said.

Kudlow, in a separate TV appearance, said Trudeau was “polarizing” and “really kind of stabbed us in the back.” The Canadian leader pulled a “sophomoric political stunt for domestic consumption, ” Kudlow said, that amounted to “a betrayal.”.

He said Trump “did the courtesy to Justin Trudeau to travel up to Quebec for that summit.

Trump followed up on Sunday with tweets calling free trade with Canada "fools trade" and said Trudeau "acts hurt when called out".

But Mr Trudeau's comments provoked a response from the USA president.

Trump also threatened to go after Canada's auto industry, a mainstay of the Ontario economy, in the same way that he has already done with its steel and aluminum sectors.

How did Trump treat Kim?

"Everybody was happy, and then he gave out a little bit of an obnoxious thing", Trump said of the prime minister. I think he should apologize to the prime minister.

G7 allies criticised Trump's decision to reject a joint communique, the BBC reported on Monday.

How should Trudeau respond to the White House's insults?

"What I saw Prime Minister Trudeau say was, I thought, fairly benign and certainly didn't warrant any attack".

Canadian dairy farmers want trade negotiators to keep their hands off the protected sector in increasingly contentious talks with the United States, however loudly U.S. President Donald Trump demands greater access, an executive with Canada's biggest dairy lobby group said on Monday.

Vanessa Coleman