President Donald Trump says he is ending "all trade negotiations" with Canada because of a television ad opposing US tariffs that he says misstated the facts, calling it "egregious behaviour" aimed at influencing US court decisions.

The post on Mr Trump's social media site came after Canadian Prime Minister Mark Carney said he aimed to double his country's exports to countries outside the US because of the threat posed by Mr Trump's tariffs.

Mr Trump's call for an abrupt end to negotiations could further inflame trade tensions that already have been building between the two neighbouring countries for months.

Mr Trump posted, "The Ronald Reagan Foundation has just announced that Canada has fraudulently used an advertisement, which is FAKE, featuring Ronald Reagan speaking negatively abou

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