Rio Tinto will sever mining links with resource-rich Papua New Guinea, relinquishing ownership of the Panguna copper mine on Bougainville island which has been closed for around 25 years after a secessionist rebellion.

The global miner said it would transfer its majority shareholding of 53.8 per cent in Bougainville Copper to an independent trustee to manage the distribution of the shares to the Autonomous Bougainville Government and Papua New Guinea.

"By distributing our shares in this way we aim to provide landowners, those closest to the mine, and all the people of Bougainville a greater say in the future of Panguna," Rio Tinto said in a statement.

In 2013 Rio Tinto investigated restarting the mine after being run off the island amid a secessionist uprising that has since subsided.

At the time, the mine was the largest single source of export revenue in Papua New Guinea and comprised about 7 per cent of the world's copper production.

Between 1972 and 1989 some 3 million tonnes of copper and 9.3 million ounces of gold were mined from Panguna.

The mine site is reported to be in disrepair and in need of extensive rehabilitation work before it could be brought back into production.

Reuters