JAKARTA. US-based mining giant Newmont Nusa Tenggara said on Thursday it had notified the government that it was invoking force majeure at its Batu Hijau copper mine, West Nusa Tenggara.

It also plans to put most of the mine’s employees on leave with reduced pay.

Newmont and fellow American miner Freeport Indonesia, which account for 97 percent of Indonesia’s copper output, are in dispute with the government over an export tax imposed in January.

The export tax has been applied to miners that export semi-finished minerals, to force them to process their ores locally and create added value for the country.

“Despite our best efforts, we have not been able to export copper concentrate since January, and we still do not have an export permit,” Newmont Nusa Tenggara CEO Martiono Hadianto said in a statement. “We are left with no option but to declare force majeure.”

Newmont will continue selling copper concentrate from storage to Indonesia’s only copper smelter, PT Smelting at Gresik, throughout 2014, according to the statement, which came after a new government drive this week to force a breakthrough.

Editor: Hendra Gunawan