The man U.S. President Donald Trump has chosen to oversee his tariff agenda says hitting Canada with 25 per cent across-the-board duties would be an emergency measure to achieve border security — and could be followed by more tariffs in the future.

General Motors, the largest producer of cars in Mexico, won’t provide details on how it would react if President Trump imposes 25 percent tariffs from the two countries.

Upon returning to office, U.S. President Donald Trump has launched numerous tariff threats. They range from broad ones - a universal tariff on foreign-imported goods - to ones aimed at specific sectors,