President Donald Trump escalated his trade war Tuesday, announcing on Truth Social that he will double the tariffs on steel and aluminum coming from Canada from 25% to 50% in retaliation for new trade restrictions put in place by the province of Ontario this week.

Trump said he would increase from 25% to 50% tariffs taking effect Wednesday for Canada after Ontario said it would hike electricity prices in the U.S.

President Donald Trump may have delayed most – though not all – of the tariffs he had imposed on Canada and Mexico, but that hasn’t stopped America’s northern neighbors from responding forcefully in retaliation.