Officials said the impetus for the move, which local media has said is contained to the Muswellbrook site, was “an extended period of declining thermal coal prices,” and post-cut, the complex will have a workforce of 1,440.

“Despite extensive work over the past two years to reset our production costs and safely improve the mine’s productivity, Mount Arthur coal must continue to significantly improve performance to be a globally competitive operation,” said James Palmer, BHP Billiton’s New South Wales Energy coal asset president.

“It is a tough time for the coal industry, but, here at Mount Arthur Coal, we’ve got a tier one resource — we believe this will leave Mount Arthur Coal on a much stronger footing,” he added.

BHP Billiton has offered support services and said it will work with its employees and the community to manage the impacts of the thermal mine’s job losses.

Last December, the producer’s New South Wales Energy Coal business, which includes Mount Arthur Coal, reported a $9 million loss for the second half of the year. In the past 18 months, global thermal coal prices have dropped an average 27%, the company added.