Chile, the world's No. 1 copper producer, is in wait-and-see mode after U.S. President Donald Trump announced a surprise 50% tariff on imports of the red metal, with the Andean nation blindsided while its top miner held out hope of exemptions.

President Donald Trump announced that the United States will impose a 50% tariff on all copper imports starting August 1. The decision threatens to disrupt a global supply chain for one of the key inputs for the American industry and a crucial commodity for the green technology transition.

WASHINGTON (Reuters) -President Donald Trump said on Tuesday he will announce a 50% tariff on copper later in the day, aiming to boost U.S. production of a metal critical to electric vehicles, military hardware, the power grid and many consumer goods.