The renewal of a seige by workers last week in defiance of an earlier brokered agreement has brought mining operations and coal conveying to a halt at the East Kalimantan site.

Kaltim Prima, jointly owned by Rio Tinto and BP Amoco, was forced to cease operations in early July during a similar seige, when it also declared force majeure.

Mining companies in Indonesia are facing a mounting wave of worker unrest over claims of unfair past treatment, particularly over land compensation.

Companies say the general breakdown of law and order in Indonesia, coupled with the reluctance of security forces to crack down hard on protests, is fueling illegal strikes.