Miner BHP Billiton said its iron ore production in the last quarter hit a record high of 27.75 million tons due to demand from China, Bloomberg reported. Output in the three months ended December 31 was up 9% compared to a year earlier. BHP also set records for aluminum and petroleum production during the same period. The firm is under pressure to report higher outputs after Rio Tinto reported production records for iron ore, bauxite, aluminum and other commodities during the December quarter. BHP, which wants to acquire Rio Tinto for US$100 billion, has until February 6 to make a formal bid. An earlier offer in November was rejected by Rio Tinto as undervaluing its mines and growth prospects.