Trump and his aides have reportedly threatened to redraw the northern border, go after Canada’s minerals and water, and cancel NORAD.

United States tariffs on Mexican and Canadian imports took effect on Tuesday. The levies, set at 25 percent by US President Donald Trump, have been followed by the doubling of duties on Chinese goods to 20 percent.

Canadian officials estimated this could add about 100 Canadian dollars ($69 in U.S. dollars) per month to the bills of each American affected.