BHP Group told workers at its vast coal operations across Queensland that the mines can no longer “compete for investment” and the company was receiving no returns from the projects.

The mines in the Australian state include some of the world’s biggest for steelmaking coal, which BHP operates in a 50:50 joint venture with Mitsubishi Development. While they brought in more than $1.67-billion in revenue during the six months through December, they were entirely unprofitable amid lower commodity prices and higher costs, according to BHP.

“Our financial performance is challenged by unsustainable royalty payments, increased production costs and fluctuating coal prices,” BHP Mitsubishi Alliance Asset President Adam Lancey said in an email to workers seen by Bloomberg. “Our ability to compete is under significant pressure.”

A spokesperson for BHP confirmed the content of the email on Tuesday.

Financing and permitting for new coal mines and expansions in Australia has become more difficult over the past few years. Banks have become increasingly reluctant to lend to the sector due to investors concerns over emissions.

CEO Mike Henry has made capital discipline a priority for BHP as costs rise, and is focusing on growth in so-called future-facing commodities such as copper. The company said in September it would shutter one of its coal mines in Queensland due to cost pressures, including royalties. The state government introduced a higher royalty regime on coal producers in 2022.

“For every dollar we have invested, we are getting zero in return,” Lancey said in the memo. He didn’t say what specific measures the joint venture would take to address the current situation.

The company will also cease operating its BHP FutureFit Academy in its current form, it said in a statement on Wednesday. The training school was opened in 2020 and is designed to provide entry pathways into mining careers via internships, traineeships and apprenticeships.

BHP is not alone in struggling to turn a profit from coal projects in Queensland. QCoal shut its Cook Colliery project last year and Bowen Coking Coal placed its Burton coal mine into administration. Virtinite which operates the Vulcan coal mine, was also put into administration this month.