The question of whether Japan should join the Trans-Pacific Partnership free-trade talks has taken center stage in the Diet as the chasm grows between TPP advocates, mainly on the side of businesses, and opponents, representing long-protected farming and fishing constituencies.

Agricultural cooperatives have turned in a petition to the government with 11.6 million signatures warning that the TPP would doom domestic farming.

Businesses meanwhile have high hopes, calling the free-trade framework a long-awaited energy shot that will recharge the sagging economy.