High seas treaty nears ratification ahead of UN Oceans Conference

Despite delays, global momentum builds for the high seas treaty with hopes for 60 ratifications in 2025.

UN Secretary-General Antonio Guterres delivers a speech during the 'International Zero Waste Day' special event in New York, United States, on March 27, 2025. Photo by Mostafa Bassim/Anadolu

By Anna Fadiah and Hayu Andini

The landmark high seas treaty designed to safeguard marine biodiversity in international waters is inching closer to becoming international law, as growing political will and recent United Nations meetings mark substantial progress — though its full enactment remains out of reach ahead of the UN Oceans Conference in June.

First adopted in June 2023 following nearly two decades of negotiations, the high seas treaty is intended to address the urgent need for protecting ecosystems in areas beyond national jurisdiction. These regions — which account for nearly half of the Earth's surface — are increasingly vulnerable to pollution, overfishing, and unsustainable development. As of now, 113 nations have signed the pact, but only 21 have officially ratified it, leaving a significant gap before the 60 ratifications required for the treaty to enter into force.

Slow but steady progress in New York

In early April 2025, delegates reconvened at the United Nations headquarters in New York for the first preparatory commission aimed at paving the way for the treaty’s implementation. Although the high seas treaty cannot be enacted until 120 days after the 60th country ratifies it, many observers noted the positive momentum gained during these sessions.

Nichola Clark, a senior official with the Pew Charitable Trusts, remarked that negotiators had moved “one step closer to shaping the institutional backbone” of the treaty. This included technical discussions on information sharing between signatories and the framework for establishing marine protected areas — key mechanisms at the core of the agreement.

Rebecca Hubbard, director of the High Seas Alliance, echoed that optimism, stating that the atmosphere at the preparatory meetings was filled with energy and urgency. “There was a lot of love in the room,” she said, highlighting that the high seas treaty represents one of the strongest tools available to ensure ocean protection on a global scale.

Eyes on Nice: June Oceans Conference as a symbolic milestone

Although the treaty won’t officially come into effect before the UN Oceans Conference in Nice, France, scheduled for June 9–13, it remains a symbolic and strategic moment for the pact’s supporters. French delegation head Sandrine Barbier emphasized the significance of a special ceremony planned on June 9 to reaffirm international commitment. She called the event “a unique opportunity to reaffirm our collective political commitment” to global ocean governance.

The summit is expected to host dozens of heads of state and government ministers and will be preceded by a scientific conference bringing together 2,000 researchers from around 100 nations. Stakeholders hope the occasion will help galvanize more countries to complete their ratification processes in time for the treaty to take effect by the end of 2025.

U.S. absence casts a long shadow

Despite the surge in global support, the absence of the United States — one of the world’s largest maritime powers — remains a glaring obstacle. While the Biden administration signed the high seas treaty, the U.S. Senate has not moved to ratify it. And in a move that stunned environmentalists and diplomats alike, former President Donald Trump issued a sweeping executive order last week, opening the door to deep-sea mining in international waters.

The order supports commercial extraction of rare earth minerals from the ocean floor, bypassing multilateral agreements and ignoring the jurisdiction of the International Seabed Authority, an organization the U.S. has never formally joined. Critics say the move undermines international efforts to protect the ocean and jeopardizes the treaty’s credibility.

“This is an insult to multilateralism and a slap in the face to all the countries and millions of people around the world who oppose this dangerous industry,” said Arlo Hemphill of Greenpeace USA, who is leading the organization’s campaign to halt deep-sea mining.

Deep-sea mining reignites global concerns

Trump’s executive order has added a new layer of controversy to an already fragile international debate. Deep-sea mining — a process that involves extracting minerals from the seabed — has drawn intense scrutiny due to its potential to irreparably damage ecosystems that remain poorly understood.

The timing of the U.S. decision is particularly sensitive, as the high seas treaty includes provisions that would regulate commercial exploitation in international waters. By ignoring those potential regulations, the Trump administration risks setting a precedent that could embolden other nations to bypass environmental safeguards.

Many see this as part of a broader trend of disengagement from global environmental frameworks. “It’s a clear sign that the U.S. will no longer be a global leader on protecting the oceans,” Hemphill said. “This is about the future of our planet, and we’re watching one of the biggest players walk away.”

Scientists and states aim for '30x30' goal

The high seas treaty is seen as a vital mechanism for achieving the global “30x30” target: an international commitment to protect 30 percent of the planet’s land and ocean by 2030. With the clock ticking, the next several months will be crucial for advocates pushing more countries to ratify the treaty.

The upcoming Oceans Conference is expected to serve as a rallying point for both scientists and policymakers, who will use the stage to emphasize the importance of halting biodiversity loss and restoring damaged marine environments. The presence of top political leaders could also help to shift momentum in key nations that have not yet ratified the treaty.

Technical hurdles and diplomatic fatigue

While enthusiasm remains high, experts warn that procedural and diplomatic hurdles continue to stand in the way. Ratification processes vary by country, and many require domestic legislative approval that can take months — or even years — to complete.

Still, the pace of technical discussions during the preparatory commission gave reason for optimism. Delegates tackled multiple issues at once, moving faster than anticipated, and laid out preliminary guidelines for monitoring and enforcement mechanisms.

“There's been some exciting progress and movement,” said Clark from Pew. “Marine protected areas — one of the most ambitious parts of the treaty — are finally starting to take shape in our discussions.”

A decisive year ahead

With 2025 shaping up to be a pivotal year for the high seas treaty, pressure is mounting on global leaders to turn symbolic gestures into binding commitments. As ocean temperatures rise and pollution levels increase, the window for meaningful action is closing fast.

The UN Oceans Conference in Nice may not mark the official birth of the treaty, but it offers a chance to show that multilateralism is still capable of addressing one of the planet’s most urgent environmental crises. Advocates say that the momentum must not be lost.

“The treaty is a lifeline for the ocean,” said Hubbard. “We cannot afford to let this opportunity slip away.”