Canberra (AAP) – A small autonomous region that hopes to become the world’s newest country is calling for energy investment as it moves to boost revenue and prop up its economy.

Bougainville overwhelmingly voted for independence from Papua New Guinea but negotiations on the transition remain ongoing years after the referendum, which PNG’s parliament is yet to ratify.

President Ishmael Toroama on Wednesday called for international investment and trading opportunities for the region as it develops.

“We acknowledge that no man is an island … we are seeking investment and trade partnerships towards the socio-economic development in Bougainville,” he told a PNG investment conference in Sydney.

“We now send out the signal that Bougainville is open for investment and trade. Come to Bougainville and be part of our journey.”

The mineral-rich island has an abundance of gold and copper, which is used to build renewable energy technology as the world transitions to net-zero emissions.

Bougainville could play an important part in the green energy transition, including through the production of green hydrogen, Toroama said.

His government signed a memorandum of understanding with UK-based green energy company Stellae Energy to identify and develop potential geothermal energy sites across the island.

The partnership is part of the autonomous region’s plan to achieve energy security and economic growth.

A feasibility study was recently completed to progress aircraft storage and refuelling facilities as the government seeks to address energy affordability amid the highest fuel prices in the region, Toroama said.

The government is also in discussions to bring Starlink to Bougainville to increase connectivity, including to outer islands, and boost economic potential.

Meanwhile, an impact assessment report of the region’s Panguna mine was released in early December and identified environmental impacts and the flow-on effects on locals.

It was the world’s most profitable copper mine in the 1970s and ’80s when operated by Rio Tinto but only a sliver of the billions of dollars of revenue went back to Bougainville before civil war stopped its operations in 1989.

Toroama said the report would serve as a roadmap towards remedy with the mining giant.

Panguna continues to create toxic waste and risks starting deadly landslides, the assessment found.

Ongoing concerns were largely unaddressed.

“Bougainville continues to stand out as a lesson, a warning, a reminder of what not to do in resource sector development,” the president said. 

Progress has been made in re-developing the mine and Mr Toroama said 2025 was the year for increased activity with advanced exploration of the Panguna project.

An abundance of direct and indirect economic opportunities stemmed from this, he said. 

The mine’s projected revenue is $US36 billion ($A57 billion) over 20 years, a significant source of potential for Bougainville’s some $A300 million budget.

PNG Prime Minister James Marape said Bougainville needed to be able to fund at least half of its budget to ensure its independence was successful.

The region’s seven per cent revenue wasn’t sufficient and needed to get to at least 50 per cent, Marape said.