Game-changing international ocean treaty comes into force

Officially known as the Biodiversity Beyond National Jurisdiction (BBNJ) Agreement, the legally binding UN treaty covers the ocean zones that lie beyond national waters (namely, the "high seas") and the international seabed area.

These regions make up over two-thirds of the ocean's surface, representing over 90 per cent of Earth's habitat by volume. This is because the ocean is deep, and most living space on Earth is underwater.

Here are some of the key things to know:

Why it matters

The BBNJ is designed to ensure that the "high seas" are managed sustainably for the benefit of all humanity.

It is also the first legally binding ocean instrument to provide for inclusive ocean governance, with provisions on the engagement of Indigenous Peoples and local communities and on gender balance.

It is hoped that, once it is fully implemented, the Agreement will make a vital contribution to addressing the so-called "triple planetary crisis" of climate change, biodiversity loss and pollution.

Speaking to UN News, Tanzanian diplomat Mzee Ali Haji, who led his country's negotiation team during BBNJ discussions, said that the agreement marks a major step in the protection of international waters.

"Everyone should bear in mind that there is now control of the activity in the high seas. For instance, when you pollute, you are responsible for your acts".

The BBNJ strengthens the current international legal framework: it builds on the UN Convention on the Law of the Sea - in effect the "constitution for the oceans" - which has set the rules for maritime and seabed exploitation and marine protection since it came into force in 1994.

It also aims to ensure the effective implementation of the Convention, including more detail on how to manage biodiversity and aligns ocean governance with modern challenges like climate change and the 2030 Agenda for Sustainable Development (the UN-brokered blueprint for solving the world's most intractable challenges).

What does 'entry into force' mean?

After the entry into force, it becomes legally binding for the 81 nations that have ratified it so far, meaning that they agree to put it into effect at the national level.

The treaty specifies that it enters into force this Saturday: 120 days after it was ratified - accepted as legally by binding - by at least 60 countries.

Who has signed up?

The countries that have so far ratified the BBNJ including several major economies, notably China, Germany, Japan, France and Brazil.

China has a particularly important impact on industries connected to the ocean (such as shipbuilding, aquaculture, fisheries and offshore oil and gas), exporting some $155 billion of ocean-related goods in 2023, according to UN trade agency figures.

Several major economies have not yet ratified

The US, the world's biggest economy, is one of the top five ranked ocean-related goods exporters ($61 billion). Although the country adopted the treaty in 2023, it is not yet ratified, and the Senate has not acted on it.

India, one of the top developing-economy exporters ($19 billion), adopted the treaty in 2024 but domestic legislation on ratification is still pending. While the UK did introduce legislation on the matter in 2025, parliament is still to ratify it.

Russia remains one of the minority of nations that has neither adopted nor ratified the treaty, citing its wish to preserve existing governance frameworks, and ensure that freedom of navigation and shipping in international waters is guaranteed.

Is this a big setback for the treaty?

Despite the reluctance of some major economies to commit fully by ratifying, Mr. Haji is positive about the impact that the BBNJ, in its current state, will have.

"Developing countries and small island countries need support," he says. "We expect that, in the future, they will accept this agreement, because it will help them. The protection of the high seas is the responsibility of all of us."

What happens next?

The door remains open for more countries to ratify, which will make it more effective.

"When you negotiate something, you can't get 100 percent people to ratify it or to accept it in one term," says Mr. Haji. "Some just observe and then, when they see the advantages, they join. I believe that, in the future others will join".

Apart from universal participation, the key to making the BBNJ work will be implementation, including acting against those who break the rules.

According to the text of the agreement, the first meeting to monitor progress on both these fronts will take place no later than one year after the Agreement's entry into force.