President Trump is warning the EU and Canada not to get any ideas about joining forces to outmaneuver his upcoming tariff announcements, saying if they team up against the U.S. they will face consequences.

President Trump on Thursday threatened to impose heavier tariffs on Canada and the European Union if they work together to “do economic harm” to the United States, hours after he said he would impose 25 percent tariffs on imported cars and car parts.

Trump threatens large-scale tariffs against Canada and EU if they form a trade-war alliance after Canadian premier Mark Carney seeks closer ties with European countries.