The company estimated 2022 coal output at 70-76 million tonnes, lower than the 78.8 million tonnes it produced last year. Coal output in the first nine moths of this year was 8.67% lower than the same period last year due to heavy rain.

The company has proposed to the energy ministry a work plan for 2023 to produce around 80 million tonnes of coal, Bumi Resources director Sri Dharmayanti said during an online briefing.

"While official guidance has not been finalized for next year, we think it can be an internal target of up to 85 million tonnes," Bumi Resources director Dileep Srivastava told the same briefing.

Srivastava said the heavy rain this year has caused Bumi's production to drop around 10%, losing roughly $1 billion in revenue.

"If the rain is manageable in 2023, we should get higher volume and add back the $1 billion revenue that we have sacrificed because of rain this year," Srivastava said.

(Reporting by Ananda Teresia and Bernadette Christina; Editing by Ed Davies)