The U.S. will exempt some elements of North American trade from a 10-per-cent baseline tariff that will take effect Wednesday night on most of its international trading partners, and will impose higher levies on goods from countries such as China and Vietnam.

A sweeping executive order signed by Mr. Trump on Wednesday orders existing tariffs related to a U.S.-declared fentanyl emergency to remain in place for Canada and Mexico, with no levies on goods compliant with the U.S.-Mexico-Canada agreement. Non-compliant products will continue to be taxed at 25 per cent, with a lower 10-per-cent rate on energy and potash.

If the fentanyl emergency is cancelled, the tariff on non-compliant goods will fall to 12 per cent.

But other products will continue to see higher tariff rates, including aluminum, steel, and vehicles. A 25-per-cent levy “on all foreign-made automobiles” will come into effect at midnight Wednesday, Mr. Trump said. He did not specify any exemption for vehicles made in Canada, or elsewhere in North America.