In June 2023, after nearly two decades of negotiations, the international community adopted the “Agreement under the United Nations Convention on the Law of the Sea on the Conservation and Sustainable Use of Marine Biological Diversity of Areas Beyond National Jurisdiction,” also known as the BBNJ Agreement. Celebrated as a breakthrough for ocean governance globally, the treaty creates a global legal framework that protects biodiversity in areas beyond national jurisdiction (ABNJ), ensures fair benefit-sharing from marine genetic resources (MGRs), and supports capacity-building for developing countries through funding and technology transfer mechanisms.

The BBNJ Agreement closes a major gap in the international legal regime by addressing biodiversity in the high seas, complements both the U.N. Convention on the Law of the Sea (UNCLOS) — under whose framework it was negotiated — and reinforces the Convention on Biological Diversity (CBD) by providing tools to implement the targets agreed under the Kunming-Montreal Global Biodiversity Framework in areas beyond national jurisdiction. Together, these instruments now provide a more complete legal foundation for protecting marine life across the entire ocean.

The Mediterranean Sea, meanwhile, stands at a crossroads. Despite its relatively small size, it’s a geopolitical and ecological hotspot, being bordered by 22 coastal states and shaped by unresolved maritime boundaries. It’s also under growing pressure from climate change, overfishing and pollution. Yet its biodiversity is exceptional: the Mediterranean covers less than 1% of the world’s ocean surface but hosts more than 18% of its known marine species, many of which are endemic.

This sea is also among the most legally fragmented: a patchwork of overlapping national jurisdictions and regional frameworks, including the Barcelona Convention, the General Fisheries Commission for the Mediterranean (GFCM) and European Union (EU) marine policies, defines governance with several gaps. Precisely because of this complexity, the BBNJ Agreement offers a unique chance for Mediterranean countries to cooperate on common ground.

By ratifying the treaty and actively engaging in its implementation, Mediterranean countries can fill some of the long-standing gaps, access international support, and demonstrate that even in politically fractured regions, multilateralism can deliver real cooperation. At a time of deep regional division, this treaty offers something rare: a peaceful, science-based platform to act on a shared environmental crisis.

Legal gaps, political tensions and the space between

Despite claims that the Mediterranean lies outside of the scope of the BBNJ Agreement, there are legal grounds to claim the contrary. Its size notably means that technically, no point lies more than 200 nautical miles (370 kilometers) from a coast, suggesting there are no traditional “high seas.” However, this misses a critical legal nuance.

While many coastal states could extend their jurisdiction through the declaration of exclusive economic zones (EEZs), many have not or have done so without mutual agreement. As a result, vast areas of the Mediterranean remain undelimited and unclaimed, existing in a legal gray zone. Under international law, these areas are considered de facto beyond national jurisdiction and therefore within the geographical scope of the BBNJ Agreement.

On top of this legal uncertainty is a dense layer of geopolitical tensions. Maritime disputes persist across the region, between Algeria and Spain, Greece and Türkiye, Israel and Lebanon, and others. In some cases, overlapping claims are combined with internal divisions, as with Libya and Palestine, making formal maritime delimitation politically charged, if not impossible in the near term. A notable example is the Italy-Tunisia dispute over the Strait of Sicily, where conflicting interpretations of past agreements have led to uncertainty over control of ecologically important waters.

This very complexity makes the Mediterranean a critical testing ground for the BBNJ Agreement. The treaty avoids sovereignty claims and enables science-based, cooperative action for biodiversity protection in contested or unregulated spaces. Rather than wait for perfect borders or political breakthroughs, countries can act now, through multilateral coordination, regional organizations and science-based marine protection. In doing so, they can model how ocean governance might move forward even when politics stand still.

Tools for conservation, equity and influence

The BBNJ Agreement provides a powerful set of tools to protect marine biodiversity in ABNJ. Among its core mechanisms are area-based management tools (ABMTs), including marine protected areas (MPAs) that can be established in ecologically significant areas.

These tools are urgently needed in the Mediterranean. Only 1.27% of its waters are effectively protected, far short of international goals. Many of the most vulnerable habitats lie outside national jurisdiction: deep-sea canyons, seamounts and migratory corridors that are increasingly threatened by climate change and human activity.

The treaty also requires environmental impact assessments (EIAs) for activities likely to harm marine ecosystems, and sets new rules for accessing and sharing benefits from marine genetic resources. Critically, it ensures that knowledge and benefits are shared equitably, including digital sequence information that might be derived from marine organisms.

Rather than creating new institutions from scratch, the BBNJ Agreement is designed to work with existing sectoral or regional bodies, such as the Barcelona Convention and the General Fisheries Commission for the Mediterranean, or, at the sectoral level, the International Maritime Organization. This offers a way to build on what’s already in place, strengthening regional governance without duplicating efforts. The “not undermining existing bodies” principle has indeed been at the core of the negotiations.

For Mediterranean countries in the Global South, especially in North Africa and the Levant, there are even more tangible benefits. Through the treaty’s capacity-building and technology transfer mechanisms, these countries can access funding, training and tools to implement conservation measures more effectively. Becoming parties to the agreement also gives them a voice in the Conference of the Parties (COP), the body that will decide how these new tools are applied, including where ABMTs are established and how benefits are shared. In short, the treaty is not just about conservation; it is also about agency, equity and long-term influence in the governance of shared seas.

Linking to 30×30

The BBNJ Agreement is also a critical mechanism for helping countries meet the global 30×30 target: the commitment to protect 30% of the ocean by 2030, which has been endorsed by nearly 200 countries under the Kunming-Montreal Global Biodiversity Framework.

Mediterranean countries have not only endorsed this target at the global level, but they have also done so through the Barcelona Convention’s Post-2020 Strategic Action Programme for the Conservation of Biological Diversity (SAP BIO) and the Post-2020 Regional Strategy for Marine and Coastal Areas and Other Effective Area-Based Conservation Measures (OECMs). These frameworks highlight the urgent need to scale up MPAs and other effective area-based conservation measures (OECMs) in the Mediterranean, including in ABNJ.

The BBNJ Agreement gives countries a way to operationalize their 30×30 commitments beyond coastal waters, filling a legal and ecological gap that has persisted for decades.

Ratification, nation by nation

Despite strong momentum globally, Mediterranean nations’ ratification remains uneven. Out of the region’s 22 coastal states, fewer than half have completed ratification; roughly one-third have signed but not yet ratified; and the rest have not taken any formal steps at all. This patchwork of engagement highlights both progress and persistent hesitation, rooted in the region’s complex political and diplomatic contexts.

This ratification gap is not merely technical; it is deeply political and symbolic. For many countries, ratification seems to hinge on strategic timing rather than legal readiness, while others face deeper structural challenges that hinder formal adoption. Most sit somewhere in between, struggling with overlapping diplomatic disputes, legal ambiguities, and fragmented domestic policymaking.

Yet the treaty’s genius lies in its flexibility, as it allows countries to cooperate without settling sovereignty disputes. It offers a platform where states can act on their shared environmental interests, even if they disagree on borders. This makes it uniquely suited to the Mediterranean, a region where diplomacy is often shaped by mistrust and history.

The European Union, now a ratifying party, continues to play a critical leadership role. By mobilizing diplomatic, legal and financial resources through its institutions and member states, the EU can help catalyze broader regional ratification and implementation.

Moment of decision

The BBNJ Agreement will enter into force only once 60 countries ratify it. With just a handful of Mediterranean states having done so, the Mediterranean risks being excluded from shaping decisions on MPA designations, genetic resource governance, and compliance mechanisms.

This is not just a legal opportunity — it is a political one. By ratifying the treaty, Mediterranean countries can claim their place at the table, influence how high seas conservation is implemented, and ensure that regional priorities are heard. Delaying ratification means giving up that voice, and possibly seeing critical decisions made by others.

But more than process is at stake. The BBNJ Agreement is a rare chance to act collectively for the health of the sea that has nourished cultures, economies and ecosystems for millennia. Protecting areas beyond national jurisdiction is not only about drawing lines on a map; it is about political courage, shared stewardship, and a long-overdue shift from fragmentation to cooperation.

The Mediterranean is a sea of history. Now, it has a chance to become a sea of progress.

Camille Loth is a marine policy expert with experience in international ocean governance and environmental diplomacy. Giuseppe Di Carlo is an ocean conservationist with 15 years of experience in marine science, conservation, and policy.

Banner image: False killer whales in the Mediterranean. Image by Vincent Kneefel / Ocean Image Bank.

Related audio from Mongabay’s podcast: An ocean governance expert discusses the high potential of the UN’s new BBNJ ocean governance treaty and also the challenges it faces, listen here:

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