Japan and the United States are in the final stage of talks on criteria for invoking safeguard measures to limit imports of U.S. beef and pork as part of the proposed Trans-Pacific Partnership trade pact, negotiation sources said Wednesday.

Presuming a final agreement is reached, the two countries are planning to put safeguard measures for beef in motion 15 years after the resulting trade accord takes effect, if the total amount of beef imports exceeds around 739,000 tons, and for low-priced pork in 10 years if total imports exceed 150,000 tons, the sources said.

In bilateral negotiations with Washington for the 12-country TPP, Tokyo has called for safeguard measures to protect domestic farmers, as it is set to expand imports of U.S. beef and pork, one of Japan's politically sensitive agricultural product categories.