Workers at Freeport McMoRan Copper and Gold Inc's mine in Indonesia will stop returning to work on Saturday if they are not paid salaries owed to them during a recent three month strike.

A union official said that hundreds of miners have been slowly returning this week to Freeport's Grasberg mine, after 8,000 workers ended a strike in mid December that has paralyzed the mine's output and shipments since September.

Union spokesman Virgo Solossa told Reuters they would stop going back to the mine if private contractors did not pay their salaries on Friday. He said that "We will stop mobilizing workers until we fully get our rights.”

Under Indonesian labour law, workers must be paid while they are on strike.

The strike ended on December 14 with a deal under which Freeport agreed to a pay increase of roughly 40% for around 8,000 union members and to a framework for a better deal for roughly 15,000 other non union workers and contractors.

But a resumption of work was delayed because of a dispute with contractor PT Kuala Pelabuhan Indonesia over possible sanctions on workers who took part in the strike. Last week KPI agreed to rehire with no sanctions about 700 workers who went on strike.

Mr Solossa said that he expected a similar dispute with other sub-contractors that emerged this week to be resolved quickly.

(Sourced from Thomson Reuters)