Markets on Wall Street and in Europe declined rapidly early Friday morning after President Donald Trump posted a pair of tariff threats on social media, one aimed at Apple and the other at the European Union.

U.S. stock index futures slid on Friday after President Donald Trump recommended 50% tariffs on the European Union, while Apple stock dropped after he warned that the company would have to pay tariffs if its phones were not made in the United States.

Stock futures slid Friday morning after President Donald Trump issued fresh tariff threats against the European Union and Apple, reigniting fears of a global trade clash and rattling investors. Dow futures were down by more than 600 points,