American Sovereignty Restoration Act of 2003

American Sovereignty Restoration Act of 2003 - Repeals the United Nations Participation Act of 1945 and other specified related laws. Directs the President to terminate U.S. participation in the United Nations (UN), including any organ, specialized agency, commission, or other affiliated body. Requires closure of the U.S. Mission to the UN.

Prohibits: (1) the authorization of funds for the U.S. assessed or voluntary contribution to the UN; (2) the authorization of funds for any U.S. contribution to any UN military operation; and (3) the expenditure of funds to support the participation of U.S. armed forces as part of any UN military or peacekeeping operation. Bars U.S. armed forces from serving under UN command.