https://arstechnica.com/tech-policy/2021/02/china-targets-rare-earth-export-curbs-to-hobble-us-defense-industry/

China is exploring limiting the export of rare earth minerals that are crucial for the manufacture of American F-35 fighter jets and other sophisticated weaponry, according to people involved in a government consultation.

The Ministry of Industry and Information Technology last month proposed draft controls on the production and export of 17 rare earth minerals in China, which controls about 80 percent of global supply.