South Korea's POSCO, the world's No.4 steelmaker, said on Thursday it was not discussing a new deal with Brazilian miner Vale on iron ore supply as its term deal remained in place.

    "There have been no further talks since we completed our negotiations with Vale in February and the term contract that we signed for the period starting on April 1 remains intact," said a spokeswoman for POSCO, which buys around one-third of its iron ore requirements from Vale.

    Vale said on Wednesday it would not confirm market rumours after the trade journal Steel Business Briefing reported that the miner demanded Chinese customers pay an additional 20 percent for iron ore from Sept. 1, citing a company e-mail. 

    Vale had negotiated a price rise with term Asian customers of between 65 percent and 71 percent, depending on the grade of iron ore, for the year beginning April 1.

    But its deal was eclipsed by Australian rivals Rio Tinto and BHP Billiton, which wrung out bigger increases from Asian mills in later negotiations based on the added savings in freight from closer mines.

    The reported additional charge would mean that the price of South System fines from Brazil would increase by 86.4 percent compared with 2007, while Carajas fines from northern Brazil would rise 2.4 percent, the journal said.