International Court of Justice: historic Advisory Opinion on the obligations of States in respect of climate change

On July 23, 2025, the International Court of Justice (ICJ) issued a historic advisory opinion, which determines the obligations of states in respect of climate change to ensure the protection of the environment. 

The opinion, issued under the request of the UN General Assembly, represents the outcome of unprecedented participation in the discussion by States and international organizations and was unanimously adopted by the ICJ judges.

The Court, underlying State’s commitments to environmental and human rights treaties, such as the Paris Agreement, the International Covenant on Civil and Political Rights, the International Covenant on Economic, Social and Cultural Rights and the Universal Declaration of Human Rights, declares that States have the obligation to protect the environment for the sake of present and future generations. 

Among States’ obligations, the opinion underlines the duty to prevent significant harm to the environment by acting with due diligence, including taking measures to reduce GHG emissions, making scientific information available and taking all the means at their disposal to protect the climate system in accordance with their capabilities and available resources. States also have the duty to cooperate with other states for the protection of the environment.  

Most importantly, the Court emphasizes that the right to a healthy environment is fundamental for the enjoyment of other human rights: without a clean, healthy and sustainable environment, many other fundamental human rights cannot be fully realized by all human beings.