United States Agricultural Products Market Access Act of 2003 - Amends the Trade Act of 1974 to direct the United States Trade Representative (USTR) to identify those foreign countries that: (1) deny fair and equitable market access to U.S. agricultural products or apply standards for the importation of U.S. agricultural products that are not related to public health concerns or cannot be substantiated by reliable analytical methods; and (2) are determined by the USTR to be priority foreign countries. Limits the identification of priority foreign countries to those that engage in the most onerous or egregious acts which have the greatest adverse impact on the relevant U.S. products.
Provides that if available information indicates that such action is appropriate, the USTR may at any time: (1) revoke the identification of any foreign country as a priority foreign country; or (2) identify any foreign country as a priority foreign country.
Provides funding for additional staff for the Office of the Assistant U.S. Trade Representative for Agricultural Affairs and Office of the Assistant U.S. Trade Representative for Monitoring and Enforcement.
Requires the U.S. Trade Representative to initiate an investigation (without waiting for a petition by an interested person) regarding any act, policy, or practice of a priority foreign country identified under this Act.