Base metal and coal mining firm South32, a spin-off from BHP Billiton, has reported a massive loss for the half-year and says it will cut more than 770 jobs across Australia.

Key points: Miner South32 to shed hundreds of jobs after $US1.75b loss

Miner South32 to shed hundreds of jobs after $US1.75b loss Worst-hit will be WA operations, followed by NSW

Worst-hit will be WA operations, followed by NSW Move 'needed' amid global commodity price slump

Move 'needed' amid global commodity price slump Most jobs expected to go before end of financial year

In the six months to the end of December the company, which demerged from BHP in May last year, lost $US1.75 billion ($2.43 billion).

It is a dramatic turnaround from the Perth-based company's $US339 million profit from the year before.

It has posted underlying earnings of just $US26 million, down from $US460 million ($640 million) on the year before.

It did manage to reduce debt by $US286 million to $US116 million ($161 million).

The company said the result was due to write downs in its coal, alumina and manganese operations, reflecting the global slump in commodity prices.

South32 chief executive Graham Kerr said the reduction would involve reorganising management in mining and refining operations.

"When we talk about the majority of people moving out of the organisation, I'd expect the majority of those would be done by the end of this financial year," he said.

"The majority of those people, if not already spoken to, they are in the process of being spoken to over the next couple of months.

"That's not an easy thing for us to do, we're decreasing our workforce by about 17 per cent, based on FY 15."

He said 4,500 jobs would have gone by end of this financial year since the company broke away from BHP.

Mr Kerr said while the company would continue to keep its eye out for cheap, distressed assets, it would not jump on anything.

He acknowledged the restructure would be difficult for employees and contractors, and support would be provided to those affected.

President and chief operating officer of South32 Australia Ricus Grimbeek said breaking the news to employees at the Worsley refinery in Western Australia had not been an easy process.

"There will be a number of people who will be spoken to in the next couple of days to complete our process," he said.

WA, NSW worst hit by job losses

Of the Australian job losses, more than half will come from Worsley, with 390 workers and contractors set to lose their jobs before the end of financial year.

South32 said production costs per tonne at Worsley reduced by 11 per cent during the half, but it was looking to reduce them even further.

Despite the job losses at Worsley, the company planned to continue increasing output from the operation by improved efficiencies.

Another 300 employees will be cut from the company's Illawarra operations, in New South Wales, while 82 will go from Australian Manganese.

The news follows an earlier announcement that 620 employees would be slashed from the company's Samancor mine in South Africa.

Total revenue for the company was down 27 per cent to $2.98 billion ($4.14 billion) from the same period last year.

BHP Billiton posted a $7.8 billion loss earlier this week.

