Opponents of deep-sea mining are mobilising to stop a United Nations body from issuing the first licenses for the controversial practice later this year, saying not enough is known about the seabed environment or the impact that mining could have on marine ecosystems.
At stake is the development of potentially vast amounts of mineral resources that could help drive the global transition to clean energy, but environmental campaigners say it could lead to catastrophic biodiversity losses.
Following is a list of the main players involved in the debate about whether deep-sea mining should go ahead.
The International Seabed Authority
The International Seabed Authority (ISA) is an independent intergovernmental body established under the authority of the United Nations Convention on the Law of the Sea (UNCLOS), to regulate mining activities on the ocean floor as well as protect seabed ecosystems.
Critics say that its dual role as mining regulator and custodian of the seabed environment is contradictory, and that the body has been leaning too far in the direction of corporate interests. They also say it lacks transparency and accountability, claims it denies.
ISA members are currently drawing up a "mining code" that will allow mining activities in the deep sea to begin, but a loophole in its rules could allow it to start approving applications by as early as July.
The Metals Company
The Metals Company (TMC) has been at the forefront of efforts to begin deep sea mining in the Pacific Ocean region known as the Clarion Clipperton Zone. It is partnering with the Pacific states of Nauru, Tonga and Kiribati to explore for deep-sea metals.
The Canada-based company has downplayed concerns about the environmental impact of seabed mining, saying that the collection of "loose-lying" polymetallic rock on the ocean floor was far less destructive than conventional terrestrial mining. It also says on its website that "difficult trade-offs must be made if we are to meet metal demand for the clean energy transition".
The tiny Pacific island nation of Nauru is expected to be the first to apply to the ISA to begin mining on behalf of TMC's subsidiary, Nauru Ocean Resources Inc. Nauru expressed its intention to do so in 2021, triggering the so-called "two-year rule" loophole, which meant that it could gain permission to start exploitation activities this year even if the mining code is not complete.
Other sponsoring nations
As many as 31 exploration licences have already been issued by the ISA, sponsored by a total of 14 nations. As well as Nauru, Tonga and Kiribati, they also include China, Russia, South Korea, India, Britain, France, Poland, Brazil, Japan, Jamaica and Belgium.
China is a major proponent of deep-sea mining, with three entities currently holding exploration licenses issued by the ISA, including the state-owned conglomerate Minmetals.
China's foreign ministry would not say whether the country was prepared to submit its own application to mine, but told Reuters in a statement that it "has always advocated a balanced approach to deep-sea development and deep-sea environmental protection."
As many as 14 countries have now called for a moratorium or suspension of all mining activities, including France, Germany, New Zealand, Costa Rica and Vanuatu.
The Deep Sea Conservation Coalition, which consists of more than 100 environmental groups (including Greenpeace, Friends of the Earth and the Worldwide Fund for Nature) has also been campaigning to stop deep-sea mining.
Greenpeace activists also confronted a British research ship in the eastern Pacific last month to protest against a mining expedition.