Canada and the European Union (EU) hit back with retaliatory countermeasures Wednesday, as the 25% tariffs on all steel and aluminum imports into the U.S. went into effect.

Canada announced new 25% tariffs on about C$29.8 billion ($20.8 billion) of U.S.-made goods, from steel and aluminum to consumer products like computers and sports equipment. Canadian Finance Minister Dominic LeBlanc said in a press conference that the new tariffs would follow a U.S. “dollar for dollar” approach and will take effect at 12:01 Eastern Time Thursday.

The European Commission, the EU’s enforcement arm, also issued retaliatory tariffs Wednesday. The commission said its tariffs would apply to U.S. goods worth up to 26 billion euros ($28.4 billion) and cover a range of products, including boats, bourbon, and motorbikes. The penalties would take effect on April 1, and a second set of countermeasures is due in mid-April after consulting with “member states and stakeholders.”

The tariffs are the latest salvo in a growing trade war between the U.S. and its major trading partners. The U.S. has launched a series of back-and-forth tariff policies that have stoked uncertainty, undermined confidence among business leaders and consumers, sent stocks tumbling, and raised fears of a possible economic downturn.

For example, Trump walked back a threat to double the tariff on Canadian steel and aluminum Tuesday after the province of Ontario withdrew its plan to impose a 25% export tax on electricity, according to reports.

Trump has also pledged to expand the trade measures on April 2 by imposing “reciprocal” tariffs on other countries that have their own levies against American products and has already doubled the tariff on imports from China.

UPDATE—March 12, 2025: This article has been updated to include Canada’s retaliatory tariffs.