Wollongong made the decision to suspend Wongawilli, located in New South Wales, after officials found another "fall" on the main belt road of the mine, according to a statement to the Australian Securities Exchange.

In March, regulators ordered mining activities at Wongawilli to cease to ensure adequate control and risk measures were in place at the mine.

The inspections that led to the order to halt activities at Wongawilli also caused regulators to open an investigation into the company and whether it was complying with Australian work safety laws, Wollongong said on April 3.

Suspending the mine will cause about 45 job cuts, mainly affecting operators, electricians, fitters and deputies, the company said on Wednesday.

Wollongong's only other mine - the Russell Vale Colliery - has been under care and maintenance since 2015, it said.

The company said it has been sustaining "significant losses" as a result of the closure and the issues at both mines, prompting its majority owner and main customer Jindal Steel and Power Ltd, along with itself, to enter talks with creditors to restructure its debt.

Wollongong has a score of 1 according to StarMine's Combined Credit Risk Model, where a rank closer to 1 out of 100 denotes the greater probability of a default in the next year.