A union official said on Monday that workers at Freeport McMoran Copper & Gold Inc's mine in Indonesia may delay returning to work, despite a deal to end a three-month strike, in the absence of a decision on the removal of about 100 workers at a local unit

The workers at Freeport Indonesia's Grasberg mine in the eastern province of Papua were supposed to gradually return to work this week to end the strike that has crippled output and exports from the world's second-biggest copper mine.

They had agreed a deal with management earlier this month on a pay rise of about 40% to end the three month strike that crippled the company's production.

Some workers held a traditional stone burning ritual and removed a road blockage over the weekend near the mine, marking the end of the longest running strike in recent Indonesian history.

But the agreement is at risk as the local unit, PT Kuala Pelabuhan Indonesia had failed to guarantee that 119 workers, who were suspended during the strike, would be rehired,

KPI has a total of 2,100 workers, mostly at the port which handles copper shipments of Freeport McMoran Copper & Gold Inc's Indonesian unit.

Mr Juarsa Oemardikarta senior manager corporate and administrative support at KPI, told Reuters 18 workers had been sacked and another 101 temporarily supended in September-October until further evaluation.

Grasberg workers may also stay away from the mine until there is a decision on another 473 KPI workers who had to sign a disciplinary statement before resuming work.

The strike at Grasberg mine harmed Freeport's total production and led the firm to declare force majeure on exports in October, helping lift global prices.

(Sourced from Thomson Reuters)