Former U.S. President Donald Trump has announced plans to impose a 50% tariff on imports from the European Union if he returns to the White House.

"If that is not the case, a tariff of at least 25% must be paid by Apple to the US."Adding uncertainty to his ultimatum, Trump later said the tariff wouldn't apply to just the iPhone but also to any smartphone made outside the US.

"The E.U., formed for the primary purpose of taking advantage of the U.S. on trade, has been very to deal with."