Stocks were mixed in early trading on Monday after President Donald Trump over the weekend issued 30% tariffs on the European Union and Mexico, rekindling tensions with two of the largest U.S. trade partners and threatening to raise consumer prices.

The EU says the U.S. is resisting efforts to strike a trade deal and warned of countermeasures if no agreement is reached with U.S. by Aug. 1.

President Donald Trump expanded his tariff threats over the weekend, calling for 30% levies on two of America’s largest trading partners: the European Union and Mexico.