Chinese steel mills are seeking a 45% iron ore benchmark price cut from Rio Tinto PLC (RTP) and a 40% cut from Companhia Vale do Rio Doce (RIO), the official Xinhua news agency reported Thursday.

The China Iron and Steel Association will soon make a statement calling for these levels of cuts from last year's benchmark rates, the report said, quoting Shan Shanghua, the association's secretary-general.

The Chinese side has called for a cut of about 40%-50% but until now, have never been specific about how much it would or has demanded of each miner.

The report didn't specify how much of a cut the Chinese would ask from BHP Billiton Ltd. (BHP), but both BHP and Rio Tinto got the same price increase last year of about 88%; in contrast, Vale got a 65% raise.

The mining majors are locked in negotiations with the Chinese over iron ore prices.

-By Chuin-Wei Yap, Dow Jones Newswires; 8610 6588 5848; chuin-wei.yap@dowjones.com