With Prime Minister Shinzo Abe determined to join negotiations for the Trans-Pacific Partnership free-trade pact, the focus has now shifted to how much deregulation Tokyo would have to sacrifice to Washington in the automobile and insurance sectors in exchange for the protection of Japan's politically sensitive farm products, experts say.

Japan is set to work on a priority list of rice and other farm produce it wants to treat as exceptions from the U.S.-led free-trade pact and chances are slim that Tokyo will demand deregulation from Washington, they say.

"So far, the fields of focus are agriculture, automobiles and insurance," said Hideo Kumano, chief economist at Dai-ichi Life Research Institute.