A license is required to export US-origin items/technology to the entity, typically reviewed under a presumption of denial (e.g. BIS Entity List). It is not an asset freeze.
Added to the BIS Entity List (15 CFR Part 744, Supplement No. 4) under the China heading, imposing a license requirement on exports, reexports, and transfers of items subject to the EAR with a license review policy of presumption of denial. Listed as 'Tongfang NucTech Technology Ltd.' with the alias 'NucTech.' Rule effective Dec 18, 2020; published in the Federal Register Dec 22, 2020.