US stocks opened significantly lower on Friday after President Donald Trump ramped up his trade fight again, slapping a tariff on Apple for foreign-made iPhones and recommending new stiffer duties on the European Union.

Apple shares shed 3.6% after Trump posted on Truth Social that iPhones sold in the U.S. must be made in the U.S. and if they are not “a tariff of at least 25% must be paid by Apple.” The move against Apple by Trump is the first against a specific company in his tariff rollout this year.

Separately, the president said trade discussions with the EU “are going nowhere” and so he’s “recommending a straight 50% tariff on the European Union, starting on June 1, 2025.”

Other big tech stocks also sank. Nvidia, Amazon, Meta, and Tesla fell about 2%; Microsoft fell 1%.