Calling the European Union "very difficult to deal with," President Donald Trump said Friday the United States would move to enact a 50% tariff on the EU.

The president threatened both Apple and the European Union with higher tariffs on Friday, saying trade talks with the Europeans had stalled.

U.S. President Donald Trump on Friday once again threatened to ramp up his trade war, recommending a 50% tariff on European Union goods starting June 1, sending European stocks tumbling.