International Steel Group Inc., the second-largest U.S. steelmaker, has notified the Industrial Revitalization Corp. of Japan of its interest in buying Mitsui Mining Co., sources said Tuesday.

ISG apparently wants to purchase Mitsui Mining to secure a stable supply source of coke amid strong global demand for the key steelmaking material, the sources said.

The U.S. company is believed to have offered more than 10 billion yen for IRCJ's 52 percent stake in Mitsui Mining, they said.

IRCJ is expected to call for bids for Mitsui Mining as early as by the end of the year. If it wins its bid, ISG will be the first foreign company to acquire a firm being helped by IRCJ.

ISG will merge with LNM Holdings NV of the Netherlands by spring to create Mittal Steel Co., which is expected to become the world's largest steelmaker. Its annual crude steel production capacity will be about 52 million tons.

IRCJ decided in October 2003 to assist Mitsui Mining after the company saw its debts exceed assets in fiscal 2002. It bought the 52 percent stake for 20 billion yen.