TOKYO (AP) -- Prime Minister Yoshihiko Noda announced Friday that Japan will participate in talks on joining a U.S.-backed Pacific Rim free trade zone, a decision strongly opposed by farmers who say the move will ruin them.
Noda said joining negotiations on the Trans-Pacific Partnership would allow Japan to tap into the region's dynamic growth.
"I've decided to start discussions with related countries toward joining TPP negotiations at the APEC summit in Honolulu," Noda told a news conference the night before his departure for Hawaii. "I believe joining the talks would serve our national interest."
The ruling party has been deeply divided over the issue, and Noda's announcement was delayed for a day by intense debate.
Big exporters say that joining the trade bloc would allow them greater access to foreign markets, promote regional investment and keep Japan competitive. But heavily subsidized farmers worry that slashing high tariffs on rice and other agricultural goods would drive them out of business.
Noda's decision "will lead to a situation that we will regret in the future," Akira Banzai, chairman of Japan Agricultural Cooperatives, said in a statement. "We should not sell off our national interest."
Although agriculture accounts for just 1.5 percent of Japan's economy, farmers have an outsized influence in parliament because of the way rural districts are represented.
"I'm fully aware that TPP could provide a big merit but is also causing tremendous concern," Noda said. "We will defend what we must protect, and try to win what we should gain."
But he added, "Japan must tap into the Asia-Pacific region's growth in order to pass on our prosperity, which we have built as a trading nation, to the next generation."
The U.S., Australia, Malaysia, Vietnam and Peru are currently negotiating to join the bloc, which already brings together the smaller economies of Chile, New Zealand, Brunei and Singapore.
Noda had said he wanted to make a decision on whether to join the bloc before the APEC summit, where President Barack Obama will host 20 other regional leaders. He said he planned to inform Obama and other participants about his decision during the meeting.
Some APEC members see the TPP as a building block for a free trade area encompassing all of Asia and the Pacific that would comprise half the world's commerce and two-fifths of its trade.
Proponents say participating in TPP would help jolt Japan's moribund economy, burdened by a surging yen and shrinking population. They also say Japan will have a say in crafting the agreement if it joins now.
Japan is worried about falling behind regional rivals in trade liberalization. Only 16 percent of Japan's trade is covered by free trade agreements, compared with 71 percent for Singapore and 36 percent for South Korea -- if a deal with the U.S. is ratified by the South Korean legislature.
Opposition lawmakers accused Noda of making a hasty decision to please Washington.
"It's a premature, snap decision that lacks principle," said Natsuo Yamaguchi, leader of opposition New Komei Party.
Japan Communist Party chief Kazuo Shii accused Noda of "putting the U.S. before (Japan's) own interest."
Critics also say Japan shouldn't increase its trade competition as it recovers from the March tsunami and nuclear crisis.
The public appears split over the issue. A recent Kyodo News poll showed supporters and opponents of the pact were nearly tied at 39 percent versus 36 percent.
Hitoshi Hayakawa, a rice farmer in northern Hokkaido, said he was disappointed by the decision, but acknowledged that Japan's agricultural sector has relied too much on government subsidies.
"I hope discussions about TPP will prompt a national debate over how we can rebuild Japanese farming and achieve food safety and sufficiency," he said in a telephone interview.
Some U.S. lawmakers are wary about including Japan in the trade talks.
Earlier this week, Sen. Carl Levin, a prominent Democratic senator, urged Obama in a letter to oppose Japan's entry unless it opens its domestic auto market.
Levin, who represents Michigan, the heart of the U.S. car industry, accused Japan of operating a one-way trade policy in which it exports millions of automobiles annually but retains nontariff barriers that stifle foreign competition at home.
Associated Press writer Malcolm Foster contributed to this report.
Copyright 2011 The Associated Press.