Claiming benefits for both sides, a visiting senior U.S. official urged Japan on Thursday to liberalize its agricultural market and launch talks on a free-trade agreement with the United States.

Speaking in Tokyo, Daniel Price, U.S. assistant to the president for international economic affairs, said that despite being close friends, the two countries are not accomplishing as much as they should be on the economic level.

Citing a study recently released by the Peterson Institute for International Economics in Washington, Price said the possible U.S.-Japan FTA would create significant economic gains for both countries.

"Japan, however, has consistently told the U.S. that it cannot consider negotiating the FTA because that might require decreasing of its protection for Japanese farmers," Price said.

He added that the absence of ambitious plans to reform the agricultural sector in Japan allowed South Korea to be the first country in Northeast Asia to conclude an FTA with the U.S.

"Japan should be our most important economic partner in Asia," Price said. "But in some respects, the U.S. and Japan are more active with other partners than with each other."

Price also expressed frustration that there has been limited progress on Japan's import restrictions on U.S. beef.

"For four years, Japan has restricted imports of U.S. beef without reasonable scientific basis," Price said. Japan continues to disregard the international scientific consensus that U.S. beef is safe, he said.

Price is in Tokyo with the American delegation to discuss economic relations between the two countries with Foreign Ministry officials.