Vanuatu is a threat to the US. At least, if you believe US President Donald Trump. Yet the US’s gross domestic product is more than 27,000 times that of Vanuatu. This tiny Pacific nation has a population of just 340,600. That is roughly three-quarters of the population of the city of Zurich. And if every single inhabitant of Vanuatu were to set out in their outrigger canoes and attack the nuclear superpower that is the US, passing the state-of-the-art US Navy, each of them would have to fight against more than a thousand Americans...

The emission of greenhouse gases is prohibited under international law

Yet the Ni-Vanuatu – as the inhabitants are known – are not attacking the US. Rather, they are defending their homeland. Not against another state, but against rising sea levels: due to the climate crisis, the low-lying islands are set to sink. The Ni-Vanuatu are fighting on the side of the law. First, together with other island states, they took their case to the International Tribunal for the Law of the Sea in Hamburg. There, the judges ruled unanimously: under the United Nations Convention on the Law of the Sea, greenhouse gas emissions constitute prohibited marine pollution.

This ban is legally binding under international law. It is therefore more binding than the Paris Climate Agreement. Under that agreement, states have committed to limiting the rise in temperature to 1.5 degrees or a maximum of 2 degrees. How each state intends to achieve this is left to its discretion. This leaves room for half-hearted measures.

Climate protection is an obligation under international law

Furthermore, Vanuatu approached the UN General Assembly and succeeded in getting it to decide to seek a climate advisory opinion from the International Court of Justice (ICJ) in The Hague. In July 2025, the ICJ reached a unanimous conclusion that was even more forceful than the advisory opinion of the International Tribunal for the Law of the Sea:

• Climate change is a massive threat to humanity, but there is a human right to a healthy, sustainable and clean environment.
• The signatory states to the Paris Climate Agreement are obliged to make every possible effort to jointly limit global warming to 1.5 °C above pre-industrial levels.
• International law also obliges states to take measures to encourage private actors to avoid emissions. The production and consumption of fossil fuels must be made unattractive, the development of new deposits must be prevented, and fossil fuels must no longer be subsidised.
• Countries harmed by climate change may be entitled to compensation.

In other words: tackling the climate crisis is not an option that one can choose to pursue to a greater or lesser extent as one sees fit. Rather, it is an obligation under international law. The UN’s highest court refers to the advisory opinion of the International Tribunal for the Law of the Sea and states: States must "use all means at their disposal to prevent activities carried out within their jurisdiction or control from causing significant harm to the climate system and other parts of the environment". This means that governments must establish ”a national system, including legislation, administrative procedures and an enforcement mechanism, and exercising adequate vigilance to make such a system function effectively, with a view to achieving the objectives."

The fact that this obligation is met with little enthusiasm in the US, among other places, is demonstrated by the statement it made – whilst still under President Biden – before the International Court of Justice: "The Paris Agreement’s object and purpose could not operate to convert the Agreement’s global temperature goal into a legally binding obligation." (ICJ, 2024)

What legal experts say

“The ICJ Advisory Opinion is considered groundbreaking, as it affirms that States havebinding obligations with respect to reducing GHG emissions, regardless of whether theyhave committed to do so in climate treaties,” writes the international commercial law firm Bird & Bird. “Moreover, States guilty of causing an internationally wrongful act have a duty of cessation of the act and must guarantee non- repetition. In addition, States may be held accountable to pay damages in case they breach these obligations to the injured state. Individuals may also invoke States’ responsibility under international human rights law and ask for reparations.”

This also applies to private companies, as the ICJ explicitly extends protective measures against greenhouse gas emissions to “fossil fuel production, fossil fuel consumption, the granting of fossil fuel exploration licences or the provision of fossil fuel subsidies”. This means: “In other words, States can be held accountable for the actions/omissions of private actors (companies) under their jurisdiction. Consequently, decisions by States that fail to address climate change or even contribute to climate change targeted at the private sector, such as issuing licences and investments, may be challenged before courts.”

Bird & Bird points out that the ICJ explicitly classifies the 1.5-degree target of the Paris Agreement as binding under international law.

“In addition, the ICJ opinion strengthens the obligations arising from theParis Agreement, stressing their due diligence character and the obligation for each State to display its “highest possible ambition»,” explains Jorge Viñuales, a professor in the Department of Land Economy at the University of Cambridge. He represented Vanuatu before the ICJ. “This conclusion of the Court is a key one, as it signals that the NationallyDetermined Contributions – each country's commitments to reduceemissions – are not simply at the discretion of individual States, butunder a genuine obligation that may be breached if such contributionslack stringency or are not implemented in good faith.”

“The ruling is disappointing for me when it comes to human rights as it remains vague on crucial points,” counters Jolein Holtz of Leiden University (NL). “Although the ICJ acknowledges that the right to a clean, healthy and sustainable environment is a human right, the Court does not say what that right involves exactly. Nor does the ICJ say what precise obligations countries have towards future generations. That’s a missed opportunity.” (Lysaght, 2025)

Vanuatu’s draft resolution calls for concrete measures

The decisions of the International Tribunal for the Law of the Sea and the International Court of Justice are advisory opinions, not judgments. They are therefore not binding. This is not enough for the Ni-Vanuatu, as they are exposed to the consequences of climate change on a daily basis, including coastal erosion caused by rising sea levels and increasingly severe storms. And based on the international advisory opinions, they know that in their struggle, they have international law on their side.

Accordingly, they want to ensure that these laws are upheld. To this end, in early 2026, together with a core group of other states, they tabled a draft resolution for the UN General Assembly for discussion during an informal consultation. In the resolution, they call on UN member states to phase out fossil fuels and to protect communities that are being forcibly displaced due to climate change. Furthermore, the draft provides for an International Register of Damage, in which losses and damages related to climate change are recorded. This refers to the advisory opinion of the International Court of Justice, according to which states can claim compensation for failure to comply with climate protection obligations. In short: states that do not consistently pursue climate targets would have to pay.

US throws a spanner in the works

On 10 February 2026, the US State Department instructed all embassies and consulates to urge their respective host countries to reject Vanuatu’s resolution. This was reported by the Associated Press, which had seen the relevant letter (Associated Press, 2026). The US "strongly objects" the resolution, as it ‘could pose a major threat to U.S. industry’. “President Trump has delivered a very clear message: that the U.N. and many nations of the world have gone wildly off track, exaggerating climate change into the world’s greatest threat,” wrote the US State Department. “This UNGA resolution is another example of U.N. overreach, part of a broader pattern of trying to use speculative climate models to fabricate purported legal obligations that seek to assign blame and encourage baseless claims, and to infer human rights obligations to which states have not agreed,” according to the cable, which tells U.S. diplomats to use it as a talking point with representatives of other countries.”

Even when the IMO was discussing measures to achieve the previously agreed net-zero target by 2050, the Trump administration threatened sanctions against states that would vote in favour of the package of measures. As a result, the decision was postponed by a year. Despite this experience, Vanuatu did not withdraw the resolution. “In the current geopolitical context, a sustained commitment to the rule of law is more important than ever,” Ralph Regenvanu, Vanuatu’s Minister for Climate Change, had previously stated. “Climate change is no exception. Adherence to the Court’s clarification of existing obligations is crucial for the credibility of the international system and for effective collective action.”

Human rights organisations and churches support Vanuatu’s resolution

“Your Excellency, We write to respectfully urge your government to support the forthcoming United Nations General Assembly (UNGA) resolution on the implementation of the Advisory Opinion on climate change issued by the International Court of Justice (ICJ),” Human Rights Watch writes to governments.

Amnesty International also calls on governments to support the resolution and ensure its adoption in its current form. “The resolution attempts to turn the ICJ’s interpretation of key legal standards into a practical roadmap for state accountability which is likely to trigger political pushback from higher income high emitting countries wary of their historical responsibility and financial liability,” said Candy Ofime, climate justice researcher and legal adviser at Amnesty International, even before the US threw a spanner in the works.

Churches are also speaking out: “The Pacific Conference of Churches (PCC) offers strong, prayerful, and unequivocal support to the Government of Vanuatu and its cross-regional Core Group for the UN General Assembly Zero Draft (30 January 2026) resolution to welcome—and, critically, to implement—the International Court of Justice (ICJ) Advisory Opinion of 23 July 2025 on the obligations of States in respect of climate change.” (PCC, 2026)

References

Farnoush Amiri, Edith Lederer, Matthew Lee (2026): Trump administration urges nations to call for the withdrawal of a UN climate proposal. AP, February 13, 2026, https://apnews.com/article/un-resolution-climate-international-court-justice-trump-31f4164aebd2b7bf8b9b4d1c89af9f50 

Amnesty International (2026): Global: Governments must use new UN General Assembly resolution to turn ICJ’s Advisory Opinion on climate change into robust action. https://www.amnesty.org/en/latest/news/2026/02/global-governments-must-use-new-un-general-assembly-resolution-to-turn-icjs-advisory-opinion-on-climate-change-into-robust-action/ 

Bird&Bird (2025): Vanuatu's Victory – International Law Requires States to Act Against Climate Change. https://www.twobirds.com/en/insights/2025/vanuatu's-victory-%E2%80%93-international-law-requires-states-to-act-against-climate-change 

International Court of Justice ICJ (2023): The General Assembly of the United Nations requests an advisory opinion from the Court on the obligations of States in respect of climate change. Press Release 19 April 2023, https://www.icj-cij.org/sites/default/files/case-related/187/187-20250723-pre-01-00-en.pdf 

International Court Of Justice ICJ (2024): Request By The United Nations General Assembly For An Advisory Opinion “Obligations Of States In Respect Of Climate Change”. Written Replies Of The United States Of America. December 2024. https://www.icj-cij.org/sites/default/files/case-related/187/187-20241220-oth-66-00-en.pdf 

International Court of Justice ICJ (2025): Obligations of States in respect of Climate Change. The Court gives its Advisory Opinion and responds to the questions posed by the General Assembly Press Release 23 July 2025. https://www.icj-cij.org/sites/default/files/case-related/187/187-20250723-pre-01-00-en.pdf 

International Court of Justice ICJ (2025):Obligations des États en Matière de Changement Climatique / Obligations of States in Respect of Climate Change / Avis Consultatif. https://icj-web.leman.un-icc.cloud/sites/default/files/case-related/187/187-20250723-adv-01-00-en.pdf 

International Tribunal For The Law Of The Sea ITLOS (2024): Tribunal Delivers Unanimous Advisory Opinion in Case No. 31 Request Submitted to the Tribunal by the Commission Of Small Island States on Climate Change and International Law. Press Release 21 May 2024. https://www.itlos.org/fileadmin/itlos/documents/press_releases_english/PR_350_EN.pdf 

Helena Lysaght (2025): The Vanuatu climate case goes far, but not far enough. https://www.universiteitleiden.nl/en/news/2025/08/the-vanuatu-climate-case-goes-far-but-not-far-enough 

Pacific Conference of Churches PCC (2026): Statement of Support: Vanuatu’s UN General Assembly Resolution to Implement the ICJ Advisory Opinion on Climate Change, Human Rights, and States’Responsibilities. https://www.oikoumene.org/sites/default/files/2026-03/Pacific%20Conference%20of%20Churches%20Statement%20of%20Support%20for%20Vanuatau%20UNGA%20ICJ%20AO%20Resolution.pdf 

University of Cambridge (2025): The 'world court' and climate change. A Cambridge professor and counsel team member for Vanuatu gives his initial views on the landmark ICJ Advisory Opinion. https://www.cam.ac.uk/stories/icj-climate-opinion-cambridge-expert