Under Trump's flip-flopping raft of tariffs, Washington placed a 10 percent tariff on Canadian energy, the major supplier to U.S. states hugging the northern border. Ford has pledged retaliatory 25 percent tariffs on Canadian electricity sent to the U.S. states of New York, Minnesota and Michigan from Ontario, to take effect on Monday.

Donald Trump has threatened to impose new tariffs on Canada, including a 250% duty on dairy products and lumber imported from the country. While the U.S. president had previously exempted some Canadian goods from tariffs,