Union estimates placed the number of jobs affected at Grasstree at 35, Construction, Forestry, Mining and Energy Union district president Stephen Smyth told ILN.

A spokesperson for Anglo American Metallurgical Coal told ILN that the numbers of employees could not be confirmed as it was still working through a review process at the site.

“Grasstree mine has completed an organisational review due to current market conditions and changed its rostering requirements,” she said.

“As a result of this, some contractor and workforce roles will be reduced over coming weeks and some redundancies will be issued.

“Anglo American is working closely with our employee representatives and our workforce throughout this process.”

Anglo is currently the world’s number three producer of metallurgical coal.

The company, which has most of its mines in Queensland, also faces an increased royalty payment from the state government.

Anglo coking coal business CEO Seamus French reportedly told the Wall Street Journal in September that cuts to production and staffing levels would be made on a case-by-case basis in its operations.

He allegedly said near-term projects across the sector would probably be delayed through the final quarter of this year and the first half of 2013.

"We are in a situation where the high prices of last year encouraged a lot of new production on to the market," French reportedly said.

"In a period of oversupply it is a natural adjustment for producers to start to trim back."

Anglo recently decided to reduce the number of operating longwalls at its Moranbah North mine from two to one next year.