Britain joins growing list of countries pledging to safeguard the global commons through historic UN agreement on marine protection
The United Kingdom has committed to ratifying the United Nations’ landmark High Seas Treaty before the end of the year, joining a global push to bring one of the most significant environmental agreements in history into force.
The treaty, officially known as the UN High Seas Treaty, aims to bring law, oversight, and conservation to nearly two-thirds of the world’s oceans — international waters that currently fall outside any single nation’s jurisdiction and remain largely unregulated. These vast expanses, covering areas beyond 200 nautical miles from any coastline, have long been described as the “wild west” of the ocean, vulnerable to overfishing, climate change, deep-sea mining, and geoengineering.
The UK’s Department for Environment, Food and Rural Affairs (Defra) confirmed its intention to ratify the treaty in Parliament by the end of 2025. The move follows sustained pressure from environmental campaigners, international leaders, and public figures, including Sir David Attenborough and Prince William, to treat ocean governance as a top global priority.
The treaty, officially known as the UN High Seas Treaty, aims to bring law, oversight, and conservation to nearly two-thirds of the world’s oceans — international waters that currently fall outside any single nation’s jurisdiction and remain largely unregulated.
“The high seas are a global commons. They belong to no one but are everyone’s responsibility,” said Hilde Heine, President of the Marshall Islands, during this week’s UN Ocean Conference in Nice, France. “This treaty is long overdue and essential to preserving the integrity and health of our oceans.”
Adopted by consensus in 2023 after nearly two decades of negotiations, the treaty still requires ratification by 60 countries before it can enter into force. The UK’s announcement came amid a surge of new commitments at the conference, pushing the total number of ratifying countries to 50 — putting the treaty tantalisingly close to the finish line.
UN Secretary-General Antonio Guterres welcomed the developments with urgency and hope. “We do not have a moment to lose,” he said. “The ocean is the lifeblood of our planet — it produces half the oxygen we breathe, nourishes billions of people, supports millions of jobs, and sustains global trade.”
The treaty is designed to introduce enforceable rules and collective decision-making mechanisms to protect the biodiversity and ecosystems of the high seas. Among its key provisions are the establishment of marine protected areas (MPAs) in international waters, shared access to marine genetic resources, and protocols to ensure environmental impact assessments for potentially harmful activities.
The treaty also outlines a framework for technology sharing and equitable benefit distribution, particularly important to smaller island nations and developing countries that currently lack the resources to monitor or regulate distant marine territories.
Environmental organisations have praised the UK’s decision to speed up ratification. “We’re tantalisingly close to a huge moment for the planet,” said Chris Thorne, oceans campaigner at Greenpeace UK. “The treaty could deliver protection on a scale we’ve never seen before.”
Despite the progress, some major players remain conspicuously absent. President Donald Trump’s administration has withdrawn US funding from several environmental initiatives, and Washington has yet to commit to the treaty, raising questions about future enforcement. However, island nations like the Marshall Islands believe the moral and legal precedents set by the treaty will be powerful even without universal participation.
While the UK has previously faced criticism for dragging its feet, Defra now says the treaty is in line with its broader marine conservation strategy. The government also announced at the conference its intention to extend the ban on bottom trawling — a destructive fishing practice — to more marine protected areas in English waters.
Campaigners argue that without regulation, the high seas risk being exploited for short-term profit at the expense of marine ecosystems and long-term planetary health. The treaty, they say, is a crucial step in shifting from chaos to collective stewardship.
If ratified swiftly, the treaty could herald a new era in ocean governance — one where no part of the planet is left outside the rule of law.
