MELBOURNE (Reuters) - Global miner BHP Billiton (>> BHP Billiton Limited) (>> BHP Billiton plc) said on Friday it would be shedding jobs at its operations in South Australia, the latest sign that miners are having to cut costs to cope with a drop in commodity prices.

The prices of oil, iron ore and copper are at their lowest levels since 2009, with oversupply in some markets and a slowing Chinese economy piling on the pressure.

"Over the past few months, Olympic Dam has been focussed on identifying opportunities to safely reduce costs in order to build a strong, viable business," BHP said in a statement. "As a result, a number of positions will be made redundant."

The miner said some workers would be redeployed at Olympic Dam, which produces mostly copper, and that as such it was not able to provide a net estimate of job losses.

State opposition leader Steven Marshall said he understood 300 jobs would go, national broadcaster ABC said in a report.

"The job losses are in the vicinity of 300, of which they hope a hundred of those will be able to be taken up with the Olympic Dam expansion plan," he said, according to the ABC report.

Olympic Dam plans to increase copper output from the second half of the year.

Benchmark three-month copper on the London Metal Exchange fell below $5,400 a tonne this week to its weakest level since July 2009. Copper has lost more than 11 percent in January and is on track for its worst month since September 2011.

(Reporting by Melanie Burton; Editing by Alan Raybould)

Stocks treated in this article : BHP Billiton plc, BHP Billiton Limited