BEIJING (AP) — China on Thursday announced rare sanctions against two U.S. defense companies over what it called their support for arms sales to Taiwan, the self-governing island democracy Beijing claims as its own territory to be recovered by force if necessary.

The announcement freezes the assets of General Atomics Aeronautical Systems and General Dynamics Land Systems held within China. It also bars the companies’ management from entering the country.

Filings show General Dynamics operates a half-dozen Gulfstream and jet aviation services operations in China, which remains heavily reliant on foreign aerospace technology even as it attempts to build its own presence in the field.

The company also helps make the Abrams tank being purchased by Taiwan to replace outdated armor intended to deter or resist an invasion from China.

General Atomics produces the Predator and Reaper drones used by the U.S. military. Chinese authorities did not go into details on the company’s alleged involvement with supplying arms to Taiwan.