PORT MORESBY: Pope Francis on Saturday urged Papua New Guinea's leaders to ease tensions with the autonomous island of Bougainville, as fears grow that a stymied bid for independence could rekindle a civil war.

Urging a "sense of responsibility", the pope told politicians and diplomats gathered in Port Moresby that cooperation could find "a definitive solution" to Bougainville's status, "while avoiding the rekindling of ancient tensions."

In 2019, 98 percent of Bougainvillians voted to secede from Papua New Guinea, their neighbours across the Solomon Sea.

That result was verified as free and fair by international observers, but has yet to be ratified by Papua New Guinea's parliament - which fears independence could destabilise their country and strip it of vast natural resources.

The referendum was the cornerstone of a 2001 peace agreement that followed a brutal decade-long civil war between Bougainville rebels, Papua New Guinea security forces and foreign mercenaries that left up to 20,000 people dead.

The 10-year war ended in 1998 was rooted in a struggle over revenues from the now-shuttered Panguna copper mine, which at one point accounted for more than 40 percent of Papua New Guinea's exports.

The mine is estimated to still hold more than five million tonnes of copper and 19 million ounces of gold - worth billions of dollars at current market prices.

Bougainville is also considered to have rich agricultural land and relatively large fish stocks.

In Port Moresby there is fear that Bougainville's departure might spark a rush of regions calling for greater autonomy from an already weak central government.

Since French explorer Louis de Bougainville arrived on the islands more than two hundred years ago, control has passed from Germany to Australia to Japan to the United Nations and to Papua New Guinea.

Many Bougainvilleans however feel a closer cultural affinity to the nearby Solomon Islands, with a strong provincial identity that differs from the tribal factions of other regions of Papua New Guinea.

 - AFP