Major supermarket firms Aeon Co. and Uny Co. will offer 30 percent to 50 percent discounts on lettuce, tomatoes and other produce items over four days starting Thursday.

The move, announced Tuesday, is to keep pace with rival Ito-Yokado Co., which has launched a similar campaign.

Aeon, operator of the Jusco supermarket chain, said it will begin the campaign at 270 outlets.

Uny, operator of the Uny and Apita supermarket chains, said its sale will be held at a total of 70 Uny and Apita outlets in Aichi, Gifu, Mie and Nagano prefectures.

Ito-Yokado began offering cut-price vegetables last weekend to stimulate demand, which had dropped after vegetable prices spiked due to unseasonably cool summer weather.

Aeon said vegetables to be discounted include potatoes, onions and carrots, but specific varieties and prices will vary store to store. The vegetable sale will be conducted nationwide, except in Kyushu and Okinawa Prefecture, it added.

Uny said produce that it will put on sale will include Nagano Prefecture-grown lettuce, priced at 150 yen; tomatoes grown in Hokkaido and Gifu prefectures, at 280 yen for four; and Hokkaido corn, at 100 yen.