U.S. President Donald Trump's announcement of a proposed 50% tariff on copper imports has raised concerns in Chile and Peru, which together account for nearly 40% of global copper production.

President Donald Trump mentioned Tuesday — almost in passing — that he planned to impose a 50% tariff on copper imports. It still hit like a bombshell, with potential to shake up U.S. efforts to expand, develop and deploy artificial intelligence.

An indicator of copper import demand in top consumer China jumped 38% on Wednesday, suggesting robust appetite for the metal, after U.S. President Donald Trump's plans for a 50% import tariff drove down benchmark prices in London.