President Biden on Thursday said he hoped Trump would rethink his plan to impose tariffs, saying it could “screw up” relationships with close allies.

Mexican President Claudia Sheinbaum spoke to President-elect Donald Trump after he threatened to impose tariffs and she hinted at retaliation in a letter.

Trump said in a post to Truth Social on Monday that one of his first executive orders would be to hit Mexico and Canada with a blanket 25% tariff. Mexico and Canada are the second and third top suppliers of goods to the U.S., according to the Office of the U.S. Trade Representative. The U.S. imports the most goods from China.