International Court Of Justice Issues Historic Advisory Opinion On Climate Change

In a landmark moment for global climate justice, the International Court of Justice (ICJ) has delivered a historic advisory opinion affirming that all governments have a legal duty under international law to take decisive action to combat climate change. The ruling reinforces a growing international consensus that protecting the climate is not optional, but a binding legal obligation.

Welcoming the ruling, United Nations Secretary-General António Guterres said: “I welcome that the International Court of Justice has issued its historic advisory opinion. They made clear that all States are obligated under international law to protect the global climate system. This is a victory for our planet, for climate justice, and for the power of young people to make a difference.”

Guterres praised the young Pacific Islanders who initiated this call to action and underscored that the 1.5°C goal of the Paris Agreement must now underpin all national climate policies.

Background to the Ruling

The ICJ’s opinion stems from a 2023 request by the United Nations General Assembly, led by the Government of Vanuatu, seeking legal clarity on the responsibilities of states under international law to protect the climate. Over 100 countries submitted evidence and legal arguments to the court.

While the opinion is advisory, it is based on an authoritative interpretation of binding international law, and will carry significant moral and legal weight in shaping global climate action.

Court’s Key Findings – The ICJ found that:

• All states are obligated to take urgent action to reduce greenhouse gas emissions.

• There is a legal duty to phase out fossil fuels to prevent severe and irreversible damage to people and the planet.

• Failure to act constitutes a breach of international obligations, particularly towards vulnerable populations and future generations.

• The court’s opinion builds upon landmark rulings from the Netherlands, South Korea, Germany, Belgium, the International Tribunal for the Law of the Sea, the Inter-American Court of Human Rights, and the European Court of Human Rights—all of which have held governments legally accountable for inadequate climate action.

Reactions from Climate Advocates and Legal Experts

Sarah Mead, Co-Director of the Climate Litigation Network (CLN), welcomed the ruling : “This ruling validates what the majority of people around the world want from their governments—meaningful climate action. As most national plans fall short of keeping us safe, more people are turning to the courts. Today, the law stands firmly on their side.”

Cordelia Bähr, lead counsel in the high-profile KlimaSeniorinnen case before the European Court of Human Rights, stated: “This is a historic moment. The world’s top courts now unanimously confirm that governments have a legal duty to protect people from the climate crisis. Governments must now step up and deliver.”

Georg Klingler of Greenpeace Switzerland added: “This opinion strengthens the KlimaSeniorinnen case and makes it clear that Switzerland—and every nation—must protect current and future generations. This ruling will spark even more people-powered climate litigation campaigns around the world.”

A Growing Wave of Climate Litigation

The ruling comes as lawsuits are currently pending in Belgium, Canada, the Czech Republic, France, Italy, the Netherlands, New Zealand, Portugal, Spain, Sweden, Taiwan, Turkey, and several other countries. These cases, fueled by civil society and legal advocates, aim to hold governments and corporations accountable for climate inaction.

A Turning Point in International Law

This decision marks a turning point in the role of international law in addressing the climate crisis. No longer can governments delay or under-deliver. The ICJ has unequivocally stated: protecting lives, ecosystems, and the global climate system is a legal obligation—not a policy choice.

The writer of this article is Dr. Seema Javed, an environmentalist & a communications professional in the field of climate and energy