After back-and-forth tariff threats that sent markets sharply lower Tuesday, the US commerce secretary and the premier of Ontario said they would meet Thursday to renegotiate the free trade treaty known as the USMCA.

President Donald Trump said he will double the tariffs imposed on steel and aluminum imported from Canada after the province of Ontario announced surcharges on electricity going into New York, Minnesota and Michigan.

The U.S. president ratcheted up a trade war with America's northern neighbor after Ontario's surcharge on electricity sold to the United States.