The ministry’s directive, which cites safeguarding national security and interests, also requires a stricter review of end-usage for graphite dual-use items shipped to the US.

The curbs strengthen enforcement of existing limits on exports of the critical minerals that Beijing began to roll out last year.

But they apply specifically to the US, in the latest escalation of trade tensions between the world’s two largest economies in the run up to President-elect Donald Trump taking office.

China’s announcement comes after the US today, launched its third crackdown in three years on China’s semiconductor industry, curbing exports to 140 companies, including chip equipment maker Naura Technology Group.

“In principle, the export of gallium, germanium, antimony, and superhard materials to the US shall not be permitted,” the ministry said.