The U.S. government has added Chinese memory chipmaker YMTC and 21 major Chinese players in the artificial intelligence chip sector to a trade blacklist.

The U.S. government added YMTC to the list over fears it could divert American technology to previously blacklisted Chinese tech giants Huawei Technologies and Hikvision. The move, laid out in the Federal Register, will bar YMTC’s suppliers from shipping U.S. goods to it without a difficult-to-obtain license.

The 21 Chinese AI chip entities being added to the trade blacklist, which include Cambricon Technologies and CETC, face an even tougher penalty, with the U.S. government effectively blocking their access to technology made anywhere in the world with U.S. equipment.

“YMTC poses a threat to our national security, so the Biden Administration needed to act swiftly to prevent YMTC from gaining even an inch of a military or economic advantage,” Top Senate Democrat Chuck Schumer said in a statement.