President-elect Donald Trump vowed Monday that on his first day in office he would impose a 25% tariff on all products coming into the United States from Canada and Mexico.

President Claudia Sheinbaum of Mexico said she and the president-elect talked about Mexico’s efforts to curb fentanyl consumption and keep migrants from reaching the border.

Donald Trump has announced 25% tariffs on Mexico and Canada. Here is how they would work and what such tariffs might mean.