BHP Billiton plans to invest $15bn (£7.7bn) on its iron ore mining operations in Western Australia’s Pilbara region to help satisfy record demand, led by China, from world steelmakers.

The Anglo Australian mining group, which is attempting to take over rival Rio Tinto , plans to invest the capital in mines and rail and port infrastructure, in order to lift its annual production from the Pilbara from 150m tonnes to 300m tonnes by 2015. It hopes to ship 120m tonnes in 2008.