Japan's centre-left government has been struggling to reach a consensus on whether to join talks on the Trans-Pacific Partnership (TPP) backed by the United States.
Prime Minister Naoto Kan will announce late Saturday his government's plan "to start talks with the countries concerned" with the TPP, major Japanese dailies the Asahi, Yomiuri and Nikkei reported, without citing sources.
But the plan, which will be put before the cabinet on Tuesday, stops short of saying whether Japan wants to become a member of the TPP or not and instead stresses "the need to gather information" on the ongoing talks, they said.
The TPP so far has just four signed-up members who have agreed to drop most tariffs and other trade barriers -- Brunei, Chile, New Zealand and Singapore.
However, the world's largest economy, the United States, is now in talks to join the group, as are Australia, Malaysia, Peru and Vietnam.
Tokyo's decision-making has gained urgency ahead of an Asia Pacific Economic Cooperation (APEC) summit in Japan this month, at which the 21 members will talk about the tricky issue of opening up their markets to each other.
Japanese newspapers last week reported with alarm that China -- the world's top exporter which months ago overtook Japan as the global number two economy -- was for the first time considering entering the talks.
Japanese business groups have urged Kan to join talks on the TPP but his Democratic Party of Japan made recommendations that the government should "decide whether to join or not (the TPP) after starting talks to gather information," fearing the impact of cheap imports on the farm sector.
Japan, citing food-security and cultural reasons, has long protected its now highly inefficient rice farmers against imports of cheaper grain from big producers such as the United States, Australia and Vietnam.