Mr. Trump is trying use tariffs to force Mexico to better guard its border with the United States, but Mexican officials say the tariffs will only hurt both countries.

President Trump moved to impose stiff tariffs on Mexico and Canada, whose leaders swiftly responded with their own levies, and accused Trump of starting a trade war that would debilitate all three economies.

American importers will pay a new 25-percent tax on goods from Canada and Mexico and a 10-percent levy on products from China, the president said.