It is considered a milestone for the protection of the seas and for international maritime law: On January 17, 2026, the High Seas Protection Agreement came into force as part of the UN Convention on the Law of the Sea. For the first time, it enables the designation of protected areas outside national waters, provides for environmental impact assessments for interventions in the marine environment and regulates the use of genetic resources. So far, 81 states have ratified the treaty and 145 have signed it.
Oceans cover almost three quarters of our planet, they are important climate buffers, contain a large part of the earth’s biodiversity and are important components of the earth’s material cycles. But climate change, environmental pollution and over-exploitation are affecting this important habitat – also because there has been a major gap in marine protection so far: While different rules apply in national waters and there are already some marine protected areas there, the high seas have so far been a largely lawless area.
A legal framework for the use of international waters
That has now changed: After almost two decades of negotiations, the High Seas Protection Agreement came into force on January 17, 2026 as part of the UN Convention on the Law of the Sea (Agreement on the Conservation and Sustainable Use of Marine Biological Diversity of Areas beyond National Jurisdiction – BBNJ). This is the first time that the international community has agreed on a comprehensive global legal framework that is intended to protect marine biodiversity outside of national jurisdiction. It provides the international community with a legally binding instrument to protect marine biodiversity and marine ecosystems, including on the high seas. “The agreement is also binding under international law. This means that states could probably sue each other if they fail to comply with it before a special chamber at the International Tribunal for the Law of the Sea,” explains Alice Vadrot, Professor of International Relations and Environment at the University of Vienna.
On June 19, 2023, the UN contracting states decided and officially adopted the text of the treaty. 145 countries have now signed the marine protection agreement, including most EU countries and the USA, but not Russia. In order for the agreement to come into force, it had to be ratified by at least 60 countries. This was the case around six months ago. After a 120-day period, the treaty is now international law and comes into force. 81 states have ratified it; this final approval is still pending for Germany, but should take place by mid-2026. Austria and Switzerland have not yet ratified the treaty either. This must now happen as quickly as possible, says McLellan: “Your participation will not only increase political weight, but also demonstrate multilateral leadership and credibility at a time when multilateralism is under increasing pressure.”
The four core topics of the High Seas Protection Agreement
Specifically, the new high seas protection agreement covers four areas. Firstly, it provides a legal framework for the first time to establish marine protected areas on the high seas. Previously, this was only possible in international waters through regional agreements or not at all. The agreement now creates the possibility of also protecting these vast areas, which make up most of the oceans. This is also important in order to achieve the goal of the global biodiversity protection agreement agreed in 2022 to protect 30 percent of land and ocean areas by 2030. A second issue is a more equitable distribution of the benefits that arise from the use of genetic resources from the sea: so far, almost only rich countries with the appropriate resources for development have benefited from them, but now a sharing of benefits should also ensure that developing countries have a share of the cake. Thirdly, the agreement provides for a transfer of know-how and marine technologies to previously disadvantaged countries.
The fourth and, after the protected areas, the most important core topic of the High Seas Protection Agreement is binding environmental impact assessments for interventions in the marine environment. In concrete terms, this means that if a state or actor plans activities in the ocean, they must demonstrate that this will not harm the marine environment. “It is important here that the obligation to carry out environmental impact assessments is not based on the location of the activity, i.e. possibly national waters, but on the possible effects, i.e. possible damage in international waters. This is a milestone in international law and an almost surprising restriction on national sovereignty,” explains Vadrot. “In the future, other states may require coastal states to carry out environmental impact assessments for activities in national waters if there is reason to believe that international waters will be negatively affected.”
Source: UN, Science Media Center, Ocean Care, Federal Ministry for the Environment