U.S. President Donald Trump said Monday that all medium- and heavy-duty trucks imported into the United States will face a 25% tariff rate starting Nov. 1, a significant escalation of his effort to protect U.S. companies from foreign competition.

Trump last month had said heavy truck imports would face new duties on Oct. 1 on national security grounds, saying the new tariffs were to protect manufacturers from "unfair outside competition" and that the move would benefit companies such as Paccar-owned Peterbilt and Kenworth and Daimler Truck-owned Freightliner.

Under trade deals reached with Japan and the European Union, the United States has agreed to 15% tariffs on light-duty vehicles but it is not clear if they will face that rate for larger vehicles.