Donald Trump has announced that he is ending "all trade negotiations" with Canada.The move is in retaliation for a TV advert in Ontario that opposed US tariffs - and on Truth Social, the president claimed it was factually incorrect. He wrote: "They only did this to interfere with the decision of the US Supreme Court, and other courts."TARIFFS ARE VERY IMPORTANT TO THE NATIONAL SECURITY, AND ECONOMY, OF THE U.S.A."Based on their egregious behaviour, ALL TRADE NEGOTIATIONS WITH CANADA ARE HEREBY TERMINATED." ...