US President Donald Trump cranked up his trade threats on Friday, targeting both smartphone giant Apple along with imports from the entire European Union, sending the global market roiling after weeks of de-escalation provided some reprieve.

Trump threatened to impose a 25 percent tariff on Apple for any iPhones sold, but not manufactured, in the United States. More than 60 million phones are sold in the United States annually, but the country has no smartphone manufacturing. He also said he would recommend a 50 percent tariff on the European Union to begin on June 1, which would result in stiff levies on luxury items, pharmaceuticals and other goods produced by European manufacturers.

Markets dropped on the news. S&P 500 futures lost 1.5 percent in premarket activity and the Eurostoxx 600 fell two percent. Shares of Apple fell 3.5 percent in premarket trading, along with shares of other technology bellwethers. Trump did not give a time frame for his warning to Apple.

"I have long ago informed Tim Cook of Apple that I expect their iPhones that will be sold in the United States of America will be manufactured and built in the United States, not India, or anyplace else," Trump said in a post on Truth Social. "If that is not the case, a Tariff of at least 25% must be paid by Apple to the U.S."

The White House has been in negotiations with numerous countries over trade issues, but progress has been unsteady.

Trump's aggressive tariffs in April, which would have raised the rate consumers and businesses would have to pay for imported goods by roughly 25 percent, sparked a selloff in US assets, including stocks, the dollar and Treasury bonds. Markets have since rebounded.

It is not clear if Trump can levy a tariff on an individual company. (Reuters)