BHP Billiton will axe almost 300 jobs from a coal mine in the NSW Hunter Valley.

The mining giant announced the 290 job cuts from its Mount Arthur mine, blaming a sharp decline in global thermal coal prices.

The company says in the past 18 months, prices for thermal coal have declined by an average of 27 per cent.

Of the axed jobs, 230 are Mount Arthur employees under an enterprise agreement with BHP, while 60 are labour hire or contractors.

It is the second time in two years the company has cut jobs at the mine, with 163 workers sacked from the Muswellbrook site in 2014.

The latest round of cuts come after BHP posted a $US5.67 billion ($A7.84 billion) loss in the six months ended December 31.

The company’s NSW Energy Coal division, which following today’s announcement will employ about 1,440 people, reported a $US9 million ($A12.04 million) underlying earnings loss for the same period.

BHP Billiton NSW Energy Coal asset president James Palmer said the cuts will put the mine on a sustainable footing for the future.

“Despite extensive work over the past two years to reset our production costs and safely improve the mines productivity, Mount Arthur Coal must continue to significantly improve performance to be a globally competitive operation,” Mr Palmer said.

“This decision was not taken lightly because we understand it will have a range of impacts on our workforce, their families and the local community.”

The CFMEU NSW Mining and Energy division has been contacted for comment.