Tokyo Steel Manufacturing Co., Japan's biggest steel maker from scrap iron, cut all of its monthly contract prices for the first time in almost a year as China's overcapacity hurt its exports.

The October price of H-beams used in building was cut to ¥70,000 ($582) a metric ton, or 9 percent lower than September, the company said Tuesday at a briefing in Tokyo. Hot-rolled coil was trimmed to ¥53,000 a ton, from ¥63,000 a ton. It was the first reduction since November last year.

"The environment of steel export markets is tougher than last month," Managing Director Kiyoshi Imamura said at the briefing, adding that conditions made it more difficult to get export contracts. "Overseas markets continued to slump as China keeps production levels high and drives exports."

In Japan, Tokyo Steel and its domestic peers face challenges from Asian rivals offering discounts. The supply of cheaper steel produced in China, South Korea and Taiwan is a negative for domestic steel prices, Imamura said.