Tweeted Trump in a series of tweets starting last night: "Please tell Prime Minister Trudeau and President Macron that they are charging the USA massive tariffs and create non-monetary barriers".
The annual G7 summit appeared to have weathered tensions over Trump's threats of a trade war on Saturday - until the US president pulled out of a joint statement while citing "false statements" by Trudeau.
Trump's feud with Trudeau actually started one day before the G7 Summit when Trump took to Twitter to call out Trudeau and French Prime Minister Emmanuel Macron but hit peak-crazy after Trump left the G7 Summit and headed off to Singapore.
It's a startling attack on the leader of the US neighbor and ally.
Trump rejected the text of a consensus statement, traditionally a paean to shared Western values and objectives under American leadership, in angry tweets from Air Force One. Canada does indeed impose a 270% tariff on dairy that has kept many USA dairy products from making their way from the U.S.to Canada.
White House Economic Adviser Larry Kudlow, who was invited by Trump to speak from the same podium, described the comments as Trump's "free trade proclamation".More news: Trump Considers Pardoning Muhammad Ali, Whose Conviction Was Already Overturned
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Trudeau later said he reiterated to Trump that tariffs will harm industries and workers on both sides of the U.S.
When Mrs Merkel was asked if she was concerned about President Trump's retaliation against European Union counter-measures by imposing tariffs on cars, she said: "First of all, we'll try and see if we can prevent this and then hope that the European Union will respond again in the same unity".
Before leaving for Singapore, Mr. Trump had delivered a stark warning to America's trading partners not to counter his decision to impose tariffs on steel and aluminum imports.
At the G7 summit, Trump has said he wants to put an end to the United States' status as the world's "piggy bank" and suggested eliminating trade barriers between allies.
Some 75 per cent of Canadian exports go to the United States, making Canada uniquely vulnerable to a United States trade war.
"According to a Canada release, they make nearly 100 Billion Dollars in Trade with USA (guess they were bragging and got caught!)".
The calamitous summit ended in disarray after Trump broadsided his allies by disavowing a joint statement the United States had agreed to.
In response to the initial tweets critical of her country and prime minister, Canada's foreign minister, Chrystia Freeland, said her nation "does not conduct its diplomacy through ad hominem attacks".