The analysis shows that, once costs, market factors, and technological challenges are accounted for, deep sea mining for Cook Islands nodules is more likely to have a negative economic return.

Juressa Lee, Greenpeace Aotearoa seabed mining campaigner says: "Deep sea mining companies that have made bold claims to try and win social licence in places like the Cook Islands are now being exposed - their sales pitch simply doesn’t add up. Scientific warnings are crystal clear: deep sea mining will damage the oceans and harm biodiversity. Millions of people across the world, including people in the Cook Islands, are concerned about the threats posed by this industry. When you add the major financial risks, it’s hard to understand why anyone is still pushing this industry at all."

Polymetallic nodules are metal-rich rocks that sit on the deep seafloor, increasingly targeted by mining companies despite scientists’ warnings of severe ecological damage.

The new report highlights several reasons why the promise of these "golden apples" - as Cook Islands Prime Minister Mark Brown described the nodules - does not hold up. The author finds that the technologies required to extract the nodules have not been commercially demonstrated, noting that operating "at depths three times greater than the Deepwater Horizon and >15 times deeper than North Sea oil, pose significant challenges to reliable operation".

According to the author, the estimated operating costs at such depths are on a par with, or higher than, their expected market value, making commercial operations unviable.

According to this expert's assessment, there are no single processing facilities worldwide capable of converting raw nodules into saleable metals, and building new plants and supply chains would involve major technical and financial risks. Market outlook is weakest for cobalt and manganese, the primary components of value in Cook Islands nodules. The expert finds Cook Islands nodules' estimated market value is only US$100-140 per dry tonne, far below the level needed to support a profitable industry.

The release of the study comes as the deep sea mining frontrunner, Belgium's Global Sea Mineral Resources (GSR) announces its plan to divest its interests in the Cook Islands and refocus on activities in the Clarion-Clipperton Zone (CCZ). GSR intends to sell its share of the joint venture company Cobalt Seabed Resources (CSR), which was established to pursue mining in the Cook Islands.

Although no buyer has been officially named, local reporting has pointed to speculation about a possible sale to American company Wetstone, a newly formed company with little public track record and who seems close to former International Seabed Authority Secretary General, Michael Lodge.

Lee says: "The future of Pacific Island nations is inextricably linked to healthy oceans - yet this future is now at risk from proposals to open the deep sea to mining, whether within national or international waters. The Pacific Ocean, and the livelihoods it sustains, must be protected.

"Resistance to seabed mining in the Cook Islands and across the Pacific is strong and persistent. Pacific Peoples will not be sidelined by corporations and powerful countries trying to impose this new form of extractive colonialism on the region.

"Alongside our allies, who want to protect the ocean for future generations, we will continue to resist wannabe miners who want to strip the seafloor, causing irreversible harm for profits that are clearly far from guaranteed."

Greenpeace urges coordinated action from Pacific Island governments to safeguard their own waters by putting a ban on deep sea mining, while a global moratorium at the International Seabed Authority is needed to defend the ocean, which is of utmost importance to Pacific People's cultural, economic and environmental wellbeing.