The Democratic Party of Japan wants to cut food imports that make up more than half of Japan's total supply, helping local farmers at the expense of growers in the U.S., under a ¥1 trillion policy.

Japan, which gets about 60 percent of its wheat shipments and 74 percent of its soybean imports from the U.S., could boost its food self-sufficiency rate to 50 percent by 2019 under the plan, according to Nobutaka Tsutsui, a DPJ lawmaker in charge of agriculture policy. That would compare with a 41 percent rate in the year that ended March 31.

The DPJ is promising to pay farmers when prices drop below production costs and achieve self-sufficiency in "important grains." Japan depended on imports for 59 percent of its food in the year ended March 31, the highest rate among developed countries.

"A DPJ-led government will try to revive agriculture in Japan by supporting every farm with cash payments," said Nobuyuki Chino, the president of Tokyo-based Unipac Grain Ltd. "The policy will help boost domestic production, although the self-sufficiency target is hard to achieve immediately."

Japan, which grows enough rice, wants to reduce dependency on overseas grain supplies to protect against volatile global prices that soared to records last year and to ensure long-term food security. The ¥1 trillion-a-year allocation, equivalent to 40 percent of this fiscal year's agriculture budget, would start from April 2011.

The DPJ plans to promote rice production as an alternative to foreign wheat in flour milling, replacing 5 million tons of annual imports with domestic output.

"It's not a realistic idea," said Charlie Utsunomiya, director at the Tokyo office of U.S. Wheat Associates. "Japanese farmers cannot produce crops that satisfy needs from local flour millers in terms of quality and quantity."

Japan should ensure supply security by maintaining relationships with traditional trading partners because the country's weather and soil are unsuitable for high-quality wheat production, Utsunomiya said.