This groundbreaking agreement addresses the critical need to protect international waters - the vast expanse beginning 200 nautical miles from coastlines that comprises roughly two-thirds of Earth's oceans.
Previously, only 1% of these waters had adequate protection, leaving them vulnerable to unrestricted fishing, pollution, and environmental degradation. The treaty, officially called the Biodiversity Beyond National Jurisdiction Agreement, emerged from UN General Assembly negotiations that began in December 2017 and was later awarded the 2025 Earthshot Prize.
The ocean crisis that prompted this action is severe and multifaceted.
The seas have become 30% more acidic compared to pre-industrial levels, devastating coral reefs and shell-building organisms.
Plastic pollution has reached alarming levels, with over 12 million metric tons entering our oceans annually, affecting 60% of marine mammals.
Scientists project that by 2050, plastic mass could exceed fish mass in our oceans.
Additionally, 37.7% of fish stocks are currently overfished, and more than half of marine species face possible extinction by 2100 if current trends continue.
The warming of ocean surfaces has accelerated dramatically, now occurring four times faster than 40 years ago, with 2024 recording the highest ocean temperatures in history. Sea levels have risen 22.8cm since 1901, and approximately 500 marine dead zones exist where pollution has depleted oxygen to levels that can't sustain life. This triple planetary crisis of climate change, biodiversity loss, and pollution threatens every aspect of ocean health.
As of January 2026, 83 countries have ratified the treaty, including China and the EU, with 145 nations having signed with intent to ratify.
Notably, Russia stands alone among major nations in neither signing nor ratifying, citing potential economic impacts on their Arctic activities.
The United States has signed but is unlikely to ratify under Trump's administration. While the UK, India, Japan, and Germany have signed, they haven't completed ratification due to slow legislative processes, complex domestic legislation, and lack of prioritisation.
The treaty establishes four crucial mechanisms:
First, it creates Marine Protected Areas in international waters, with clear pathways for proposing new zones.
Second, it requires environmental impact assessments for activities that could harm marine ecosystems, including carbon removal projects.
Third, it establishes rules for sustainable resource management and shared benefits of marine resources.
And fourth, it promotes knowledge and technology sharing, particularly with low-income countries, to ensure equal participation in high seas governance.
Implementation details will be refined at the upcoming Conference of the Parties this autumn, focusing on achieving the goal of protecting 30% of world oceans by the end of the decade.
The conference will establish permanent bodies and a secretariat to administer the treaty and ensure its success, including setting up institutions, decision-making processes, and monitoring systems.
Rebecca Hubbard, Director of the High Seas Alliance, emphasised the treaty's importance for future generations, stating, "Protecting it really does mean protecting our future."