WASHINGTON —  The Bush administration has imposed sanctions against companies in Iran (search) and China for weapons proliferation activities.

The Iranian firm was Shahid Hemmat Industrial Group. The other was the North China Industries Corp (search).

Public documents disclosing the sanctions were made available on Thursday. The effective date of the sanctions was May 9.

No information was given about the destination or the type of technology that was exported by the two companies. Efforts to obtain additional information from State Department (search) officials were unsuccessful.

The sanctions essentially ban U.S. trade with the entities and all U.S. government dealings with them for two years.