TOKYO (Nikkei)--Japan's Fair Trade Commission is expected to move forward with its antitrust review of BHP Billiton Ltd. (BHP) and Rio Tinto Group's plan to integrate their Australian iron ore operations, the Nikkei reports Tuesday. The initial 30-day review period ends Friday, but the commission sees the need to examine the potential market implications more closely, and is therefore conducting a secondary screening. It will request additional information from the two U.K.-Australian mining giants as early as that day and issue a decision within 90 days. The two companies supply about 60% of the iron ore that Japan consumes. Domestic steelmakers have argued that an integration could lead to higher prices and hamper fair competition. Three companies -- BHP, Rio Tinto and Brazil's Vale SA (VALE) -- control about 70% of the world's iron ore market. The planned integration has raised concerns that the resulting two suppliers would gain pricing leverage. BHP and Rio Tinto announced last December that they plan to establish an iron ore joint venture. Antitrust authorities in Australia, the European Union, China, South Korea and elsewhere are reviewing the plan. Australia has postponed the announcement of its results, which was slated for July 22. Authorities around the world may be coordinating the timing of their decisions. The Fair Trade Commission most recently conducted a secondary screening in 2007, when it examined merger plans for measurement-equipment manufacturers Topcon Corp. (7732.TO) and Sokkia Co. (END) Dow Jones Newswires July 12, 2010 13:09 ET (17:09 GMT)