China, the world’s top producer and exporter of graphite, announced October 20 it will soon require export permits for some graphite products in an effort to protect national security. The Chinese Ministry of Commerce said that the new requirements will not target any specific countries, according to Reuters.

Under the rule, which will be enforced starting December 1, exporters will have to apply for permits to ship two different types of graphite, including natural flake graphite and its products as well as high-purity, high-hardness and high-intensity synthetic graphite.

The Chinese commerce ministry said the decision to curb graphite exports was “conducive to ensuring the security and stability of the global supply chain and industrial chain and conducive to better safeguarding national security and interests.”

China refines over 90% of the world’s graphite into a material used in almost all electric vehicle battery anodes, a negatively charged portion of a battery. Japan, India, South Korea and the U.S. are some of China’s biggest graphite purchasers, according to Chinese customs data.

“This bold and unexpected move by China in graphite has taken us by surprise, arriving far sooner than anyone could have predicted,” said Kien Huynh, the chief commercial officer of Alkemy Capital Investments, a London-based holding company that develops projects in the critical minerals and energy transition sectors.

Prior to this announcement, three types of “highly sensitive” graphite items had been under temporary controls, according to China’s commerce ministry. The country also dropped provisional curbs on five less sensitive graphite items used across numerous industries.