What does China’s host bid mean for the High Seas Treaty?

Source: The Conversation – Canada – By Philippe Le Billon, Professor, Geography Department and School of Public Policy & Global Affairs, University of British Columbia

Delegates are meeting in New York for the third session of the preparatory commission (PrepCom 3) on the Agreement on Marine Biological Diversity of Areas beyond National Jurisdiction (BBNJ), also known as the High Seas Treaty.

After nearly 20 years of negotiations, United Nations member states adopted the treaty in June 2023. When it opened for signatures that September, 67 countries signed immediately. In January 2026, Morocco and Sierra Leone then became the 60th and 61st states to ratify, triggering the treaty’s entry into force.

The treaty is now international law. At the time of writing, 145 countries have signed and 85 have ratified.

The third session of the preparatory commission must now work through how the treaty will actually function. A key question in corridor conversations is: who should host the secretariat?

Every international treaty needs an institutional home. The High Seas Treaty is no different. It requires a secretariat to co-ordinate between parties, service meetings and manage information.

For months, Belgium and Chile were the only contenders, their bids quietly taking shape in the background of treaty negotiations. Then, in January 2026, China submitted a formal bid with Xiamen as the proposed host city. That announcement changed the optics of the negotiations.

The geography of diplomacy

Where that secretariat sits may be seen as an administrative question, a matter of office space and convenience. It is not.

The location of secretariats, and diplomatic venues in general, shapes how they function in practice. It influences who gravitates toward the institution and which delegations can afford to attend. It sways what issues get quietly elevated and what institutional culture takes root. Location is a form of proximity and proximity is a form of influence.

Belgium has put forward Brussels, pointing to its dense ecosystem of international organizations and more than 300 diplomatic missions.

Chile has offered Valparaíso on an equity argument: Latin America has never hosted a universal-membership environmental secretariat and the Global South deserves a seat at the table.

China’s late entry adds a strong contender to the process.

Concerns about China’s influence

China has more at stake in how the high seas are governed than almost any other state. It has the world’s largest distant-water fishing fleet and has faced sustained international criticism over illegal, unreported and unregulated fishing. It also holds more deep-sea mineral exploration contracts through the International Seabed Authority than any other nation.

It has been among the most assertive in defending its maritime claims, even when those claims have been rejected by international courts, including through declaring a “nature reserve” on the disputed Scarborough Shoal in the South China Sea.

Though fishing controversially remains largely outside its scope, the BBNJ agreement intervenes in key pressure points, most notably through enforceable marine protected areas and new environmental standards for activities that have historically escaped meaningful oversight.

For some observers, that combination makes the secretariat bid difficult to reconcile. Lyn Goldsworthy, a veteran Southern Ocean researcher at the University of Tasmania, has pointed to China’s reluctance over the creation of marine protected areas in the Antarctic high seas. “If they are in that influential [position],” she told Dialogue Earth, “they can slow things down.”

Analysts at India’s National Maritime Foundation have raised the further risk of what they call procedural drift, the idea that formally neutral administrative practices can quietly embed particular governance norms over time.

However, the case is less clear-cut than it looks.

Giving China a stake in the treaty’s success

Skepticism about China’s bid is understandable, but the case against it is weaker than it first appears. Begin with the international picture. Li Shuo, director of the China Climate Hub at the Asia Society Policy Institute, has described the bid as a “significant escalation” in China’s engagement with global governance, one that signals the Chinese want to play an active role in shaping international rules.

If China’s institutional credibility is visibly tied to BBNJ’s success, it has more reasons to want the treaty to function. China has ratified the agreement. It joined the Port State Measures Agreement, the principal instrument targeting illegal fishing, despite late accession and uneven implementation.

Its navy is the fastest-growing maritime force in the world. Its financial, infrastructural and human capacity to run a serious international institution is not in question.

There is possibly an even more important dimension. Scholars focused on Chinese fisheries governance have documented the persistent tension between central government policy and the behaviour of provincial authorities and distant-water operators, a gap that domestic regulation has struggled to close.

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China is struggling to control its provinces as they expand distant-water fishing

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International treaty commitments can, in principle, function as a mechanism for central governments to exert leverage that internal channels cannot easily provide. Whether the BBNJ treaty might operate that way for China is an open question, but it is one worth taking seriously.

A China genuinely embedded in the framework may behave differently within it than a China left on the outside. The UN’s 30-by-30 target to protect 30 per cent of the world’s oceans by 2030 depends heavily on what happens in the high seas. So does any serious effort to crack down on illegal fishing or establish enforceable marine protected areas in international waters.

None of this is a straightforward argument for or against China hosting. It is a narrower claim: that the case against it is weaker than it first appears because it assumes that Chinese involvement would inevitably hollow out the treaty’s environmental ambition. That assumption is not obviously correct.

What conditions that would make the treaty work rather than fail are not mysterious. The secretariat would need genuine independence in its leadership. Governance structures would need to be transparent and enforceable. The treaty culture would need to be robust enough to resist pressure from the host state and to be responsive to all parties. These are demanding conditions. They are also conditions being negotiated right now.

What is actually at stake

The formal decision on where to locate the secretariat will be taken at the first Conference of the Parties, expected in early 2027. The institutional architecture being built at PrepCom 3 will shape what kind of institution the secretariat becomes before that vote is ever taken.

The governance rules and independence provisions being drafted now will determine whether the hosting question is a story about institutional capture or about the diligent implementation of a treaty that covers nearly half the planet.

The BBNJ agreement is a test of something larger than ocean governance. It is a test of whether international institutions can still function as common ground as the United States withdraws from international organizations and treaties.

Where the secretariat sits is not a technicality. It is about whether the high seas remain a global common in practice, not just in name, through an institution operating with independence, credibility and authority.

The authors do not work for, consult, own shares in or receive funding from any company or organisation that would benefit from this article, and have disclosed no relevant affiliations beyond their academic appointment.

– ref. What does China’s host bid mean for the High Seas Treaty? – https://theconversation.com/what-does-chinas-host-bid-mean-for-the-high-seas-treaty-279317