Donald Trump has ordered an increase in tariffs on Canadian steel and aluminum and threatened to impose more levies, after Ontario yesterday slapped a 25% surcharge on electricity exports to three US states.

In a lengthy post on Truth Social, Trump said he would “permanently shut down the automobile manufacturing business in Canada” if the country did not end unspecified tariffs it had placed on US goods:

Based on Ontario, Canada, placing a 25% Tariff on “Electricity” coming into the United States, I have instructed my Secretary of Commerce to ad an ADDITIONAL 25% Tariff, to 50%, on all STEEL and ALUMINUM COMING INTO THE UNITED STATES FROM CANADA, ONE OF THE HIGHEST TARIFFING NATIONS ANYWHERE IN THE WORLD. This will go into effect TOMORROW MORNING, March 12th. Also, Canada must immediately drop their Anti-American Farmer Tariff of 250% to 390% on various U.S. dairy products, which has long been considered outrageous. I will shortly be declaring a National Emergency on Electricity within the threatened area. This will allow the U.S to quickly do what has to be done to alleviate this abusive threat from Canada. If other egregious, long time Tariffs are not likewise dropped by Canada, I will substantially increase, on April 2nd, the Tariffs on Cars coming into the U.S. which will, essentially, permanently shut down the automobile manufacturing business in Canada. Those cars can easily be made in the USA!

Ontario’s addition of a 25% electricity surcharge affects New York, Minnesota and Michigan, which receive electricity from the province. Here’s more about that: