Ontario says it's tacking on a 25% surcharge to electricity exports to the U.S.

Ontario, Canada's most populous province, is adding a 25% surcharge to all electricity exports sent to the U.S. as part of retaliation against the Trump administration's tariffs on Canadian products.

The 25% surcharge will be effective as of March 10, and will affect consumers and businesses in Michigan, Minnesota and New York, the province said in a Monday statement. The new fee will add $400,000 in daily costs for U.S. homes and businesses, it added.

"President Trump's tariffs are a disaster for the U.S. economy. They're making life more expensive for American families and businesses," Premier Doug Ford said in the statement. "Until the threat of tariffs is gone for good, Ontario won't back down. We'll stand strong, use every tool in our toolkit and do whatever it takes to protect Ontario."

Mr. Trump's 25% tariffs on imports from Canada and Mexico went into effect last week, although on Thursday he said he would delay the levies by one month, until April 2.