An Indonesian Government audit report says the giant Freeport-McMoRan Copper and Gold mine operator in Papua should lower its maximum daily production at its Grasberg mine to reduce environmental damage.
A member of the auditor's team, Witoro Soelarno, says the mine should reduce its production by up to one third from the current cap of 300,000 tonnes of ore per day.
Mr Soelarno told the news agency Bloomberg that the group hopes the audit results are implemented this year.
Indonesia initiated the audit after local activists last year called for a shut down of the Grasberg mine, accusing Freeport of not doing enough to benefit local people.
In 2006, a team of legislators inspecting Grasberg's open-pit mine claimed they had found environmental violations that allegedly threaten the area's ecosystem.