SYDNEY (Dow Jones)--Rio Tinto Ltd. (RIO.AU) said Wednesday it has arranged US$200 million in funding to expand its iron ore operations in Western Australia state's Pilbara region. The money would be spent on dredging work to assist in the expansion of Cape Lambert, a port in the eastern Pilbara, and would help increase the capacity of Rio's Pilbara operations to 330 million metric tons per year by the first half of 2016, the company said in a release to the Australian Securities Exchange. However, Rio Tinto Iron Ore and Australia Chief Executive Sam Walsh warned that continuing uncertainties remained around the Australian government's mine tax plans. "White the Australian government's decision to abandon its Resource Super Profits Tax in favor of the proposed Minerals Resource Rent Tax was a major step forward, we remain cautious over what legislation will finally be in place," he said. -By David Fickling, Dow Jones Newswires; +61 2 8272 4689; [email protected] (END) Dow Jones Newswires July 13, 2010 20:07 ET (00:07 GMT)