President Donald Trump’s plan to impose a 25% tariff on all imported aluminum could cost 100,000 American jobs, the CEO of one of the largest US aluminum makers warned on Tuesday.

Looming aluminum tariffs have put US makers of everything from cans to cars on edge. But as long as they’re willing to pay enough of a premium, the metal is likely to continue flowing across the northern border.

The aluminum company views a 25% tariff on aluminum imports resulting in about 20,000 direct U.S. industry jobs being cut and as many as 80,000 indirect jobs being eliminated, Chief Executive Bill Oplinger said.