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How Australia shaped the ambitious High Seas Treaty

The story behind 20 years of quiet Australian diplomacy to rewrite rules for 70% of the world’s oceans.

The BBNJ Agreement transforms the way in which approximately 70% of the world’s oceans is understood, protected, managed and utilised (Sebnem Coskun/Anadolu Agency via Getty Images)
The BBNJ Agreement transforms the way in which approximately 70% of the world’s oceans is understood, protected, managed and utilised (Sebnem Coskun/Anadolu Agency via Getty Images)

In a year that commenced with the United States, through its military intervention in Venezuela and abduction of a sitting head of state, breaching fundamental tenets of the United Nations Charter and international law, it is easy to claim that international law is now irrevocably broken, the United Nations increasingly irrelevant, and multilateral diplomacy no longer feasible.

Certainly, the implications of these actions will be the focus of diplomats, experts and international lawyers for decades to come.

In this intense, fast-moving global security environment, where the UN Security Council is yet again constrained by the fact that it is a veto-wielding permanent member whose actions are in serious question, it would be understandable – but unfortunate – to miss a major positive result arising from decades of careful multilateral work within the framework of the United Nations General Assembly.

On 17 January 2026, the Agreement on the Conservation and Sustainable Use of Marine Biological Diversity of Areas beyond National Jurisdiction (BBNJ Agreement) – often referred to as the High Seas Treaty – came into force. The threshold for its entry into force, that 120 days had passed since 60 state ratifications, had been reached.

To describe this as a major advance in multilateral law-making would be a considerable understatement. The treaty negotiations through various UN General Assembly informal and formal mechanisms, open to all 193 UN member states, had taken more than 20 years to conclude, and a further two years to come into force generally.

The BBNJ Agreement changes the very understanding of “freedom of the high seas”.

The BBNJ Agreement’s objectives are ambitious: “to ensure the conservation and sustainable use of marine biological diversity of areas beyond national jurisdiction for the present and in the long term, through effective implementation of the relevant provisions of the United Nations Convention on the Law of the Sea (UNCLOS) and further international cooperation and coordination.”

While this language dutifully recognises the foundational importance of UNCLOS and its specific section on the high seas, in reality the BBNJ Agreement transforms the way in which this massive area – approximately 70% of the world’s oceans – is understood, protected, managed and utilised. Entry into force of the BBNJ Agreement changes the very understanding of “freedom of the high seas”.

The agreement establishes a comprehensive global framework for conservation and sustainable use covering both the high seas and the seabed beyond national jurisdiction. It seeks to cover gaps not addressed or not sufficiently addressed, and in some cases not understood at all, at the time of negotiation of both the 1982 UN Convention on the Law of the Sea and its 1994 Agreement.

Delegates celebrate the adoption of an agreement by consensus at the Fifth Session of the Intergovernmental Conference on Marine Biodiversity in Areas Beyond National Jurisdiction in June 2023 at UN headquarters, New York (Eskinder Debebe/UN Photo)
Delegates celebrate the adoption of an agreement by consensus at the Fifth Session of the Intergovernmental Conference on Marine Biodiversity in Areas Beyond National Jurisdiction on 19 June 2023 at UN headquarters, New York (Eskinder Debebe/UN Photo)

The BBNJ Agreement creates area-based management tools, including establishment of a network for marine protected areas in the high seas. In practice, areas beyond national jurisdiction most likely to be put forward for protection will include deep sea-bed areas containing hydrothermal vents, seamounts, and the unique biodiversity found in and around such areas. The possible impact on biodiversity of activities on ocean floor areas, such as deep-sea trawling and mining in areas beyond national jurisdiction will no doubt be a focus. It will be important to clearly delineate the role of the new BBNJ framework from that of the International Seabed Authority, which manages the non-living (mineral) resources in areas beyond national jurisdiction.

More generally, where multilateral regimes which impact on areas beyond national jurisdiction already exist, an obligation ensues for states that are parties to the BBNJ Agreement to cooperate.

The BBNJ Agreement requires environmental impact assessments for planned activities in the areas covered – a massive change to previous approaches. The Agreement provides a framework for the management and use of marine genetic resources from areas beyond national jurisdiction, requiring transparency around collection and storage, open access to such scientific results, and the fair and equitable sharing of such resources.

The BBNJ Agreement also establishes a framework for capacity building and transfer of maritime technology to assist developing states to participate fully.

Given the degree of ambition and complexity, and the range of interests engaged, it is perhaps unsurprising that negotiations stretched over two decades.

A final text was agreed on 19 June 2023. The treaty reached the threshold of 60 ratifications two years later, on 19 September 2025. More than 25 additional states have now joined.

Despite this momentum, and the passage of necessary domestic implementing legislation, it is unlikely Australia will formally become party until August 2026.

The delay in ratification apparently came down to delay in securing the necessary domestic legislative changes required.

Australia has long claimed a global leadership role on oceans issues, including in the development of the BBNJ Agreement. The fact that Australia has been unable to ratify by now is unfortunate.*

This delay should not, however, be seen as indicating any particular concerns arising during Australia’s preparation for ratification. In fact, in recent years Australia had expressed its support for the treaty repeatedly and at the highest levels. In March 2023, Foreign Minister Penny Wong said about the general international agreement of the final treaty text, “the new global oceans treaty is a remarkable milestone to protect the world’s oceans”. Australia’s subsequent signature of the treaty on 20 September 2023, the day it was opened for signature, underlined that commitment.

Following October 2024 hearings, the Joint Standing Committee on Treaties was unanimous in its recommendation that Australia ratify the treaty.

The delay in ratification apparently came down to delay in securing the necessary domestic legislative changes required to ensure effective implementation of the treaty’s requirements, rather than any change in priorities or policy approach.

In fact, despite the delay, Australia’s leadership continues. A senior Australian official is currently co-chairing the Preparatory Committee meetings that have been taking place since the treaty entered into force generally.

Recent statements don’t quite do justice to the crucial role Australia has played over more than two decades in proposing and then negotiating a comprehensive treaty dedicated to protection and sustainable use of high seas.

Australia’s publication of its Oceans Policy on 23 December 1998 was a world first – an effort to establish an integrated comprehensive policy and management framework covering all of Australia’s ocean areas. To quantify, Australia has acknowledged rights to an exclusive economic zone (EEZ) amounting to over 8.1 million square kilometres, plus an additional area of extended continental shelf (ECS) amounting to a further 2.5 million square kilometres. This area – which does not include Australia’s claimed EEZ and extended continental shelf areas deriving from the Australian Antarctic Territory – amounts to the third-largest such EEZ area in the world.

Publication of the Oceans Policy inevitably raised the question for Australia of how such a vast area within national jurisdiction – now subject to unprecedented regulation – would interact with even more vast yet lightly regulated areas beyond jurisdiction.

At the same time, new deep-ocean scientific discoveries were coming to the surface, including details of completely new biodiversity and habitats reliant on deep-sea hydrothermal vents rather than photosynthesis. Australian and other scientists and fishing operations were also reporting previously unknown phenomenon of highly biodiverse seamounts in high seas areas in both Indian and Pacific Oceans.

Deep sea chimneys at Champagne vent site, NW Eifuku volcano in Japan's Volcano Island chain (Bob Embley/NOAA PMEL)
Deep sea chimneys at Champagne vent site, NW Eifuku volcano in Japan's Volcano Island chain (Bob Embley/NOAA PMEL)

Australia’s first objective was to educate – that there was a potentially massive area of marine biodiversity beyond national jurisdiction that was not currently scientifically understood, and which was not covered by existing UNCLOS frameworks.

A four-day high-level conference was hosted and funded by Australia in Cairns in June 2003, drawing representatives from a select number of states, high-level UN officials, academics, scientific experts and selected NGOs from across the world for intensive discussions about the nature of the challenges and possible ways forward. To the author, a participant in that conference, it certainly appeared that by the end of those four days the need for action towards a framework for conservation and sustainable use of areas beyond national jurisdiction was understood.

Australia then moved quickly (in multilateral terms). Australia’s Permanent Representative to the United Nations, New York, formally drew the report of the Cairns conference to the attention of then UN Secretary-General Kofi Annan, thereby informing the UN Secretariat and all UN member states of Australia’s intentions.

Australia, working with Pacific Islands Forum colleagues, then sought to secure a provision in the next annual General Assembly Resolution on the Law of the Sea (2003) that for the first time referred to the need for conservation and sustainable management of areas beyond national jurisdiction. The resolution further proposed that the next UN Informal Consultative Process on the Oceans and the Law of the Sea (UNICPOLOS) would focus on “new sustainable uses of the oceans, including the conservation and management of the biological diversity of the seabed in areas beyond national jurisdiction.”

While there was some pushback from states keen to ensure that the definition of, or action on, high seas areas set out in UNCLOS was not further defined or amended, those promoting the UNICPOLOS discussion ultimately prevailed.

Crucially the Australian delegation to the UN in New York managed to secure broad agreement that an Australian official – a marine biodiversity policy expert – would chair the meetings.

At the subsequent UNICPOLOS meeting in May 2004, the Australian chair worked with the UN Secretariat to bring together leading scientists, policymakers and academics to present their work to assembled diplomats. States responded, demonstrating various degrees of support. The need for action was broadly accepted.

This led to a decision by member states, through that year’s UN Resolution on the Law of the Sea, to establish a working group to consider a wide range of high seas-related issues.

Over the next three years, under the leadership of the Australian chair, states engaged in the informal discussions moved gradually towards a realisation that a new international regime – or at least a significant augmentation of UNCLOS – was required to ensure effective conservation and sustainable management of a massive area of the world’s oceans.

It took almost two decades to move from this point to adoption of a final treaty text.

Three dolphins at play underwater (Talia Cohen/Unsplash)
A gradual realisation came about that a new international regime was required to ensure effective conservation and sustainable management of a massive area of the world’s oceans (Talia Cohen/Unsplash)

As formal negotiations progressed, Australia found that, in addition to its leadership for a strong outcome, it had specific interests to protect.

Australia was determined to ensure that establishing a global regime for the areas beyond national jurisdiction did not lead to a weakening or undermining of existing rules already regulating some component of the high seas. Australia had a vital interest in ensuring that the text of the treaty acknowledged the role of existing regional fisheries management arrangements, such as the Convention on the Conservation and Management of Highly Migratory Fish Stocks in the Western and Central Pacific Ocean and the Southern Indian Ocean Fisheries Agreement.

Also crucial for Australia was to ensure that the treaty did not undermine in any way Australia’s Antarctic interests, including in the Antarctic Treaty and the Convention on the Conservation of Antarctic Marine Living Resources (CCAMLR), the latter of which had long provided a workable form of high seas marine resource management.

The final text addressed both issues to Australia’s satisfaction.

Australia’s decision to ratify the BBNJ Agreement, albeit belatedly, is welcome. The decision brings back into alignment Australia’s assertions that it has long been an oceans leader with the reality, including its current role in leading diplomatic efforts post-entry into force. It should now enable some informed reflection on Australia’s central role in establishing this monumental multilateral regime.

Above all, the experience has demonstrated that in some cases careful, determined multilateral negotiation can still find solutions to massive global challenges. Eventually.

* This section was updated to correct the status of Australia’s ratification.




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