US stocks fell after Nvidia revealed costly new curbs on chip exports to China, and investors grappled with uncertainty over President Trump's trade policy.

Wall Street index futures dropped on Wednesday and chip darling Nvidia slumped after the company flagged steep charges from new U.S. curbs on chip exports to China, fuelling worries about the fallout of an escalating trade war.

Asia-Pacific markets fell this morning after the U.S. barred Nvidia from shipping its H20 AI chip to China, intensifying the trade war between Washington and Beijing. Semiconductor companies declined more broadly on Trump's tightened export controls on Nvidia.