US President Donald Trump said late on Thursday that he was ending "all trade negotiations" with Canada because of a television ad opposing US tariffs that he said misstated the facts and called "egregious behaviour" aimed at influencing US court decisions.

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

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

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

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