External publications

From principle to obligation: ICJ’s opinion on climate change and implications for African countries

Tamasiga, Phemelo / Onyeaka, Helen
External Publications (2025)

in: Megatrends Spotlight 60

What happens when the world’s highest court declares climate change not just a political challenge but a matter of international law? On 23 July 2025, the International Court of Justice (ICJ) issued a landmark advisory opinion that could redefine the global climate order. The momentum for this case began with a youth-led global campaign spearheaded by Pacific Islands Students Fighting Climate Change (PISFCC) and World’s Youth for Climate Justice (WYCJ). They mobilized more than 1,500 civil society groups worldwide and successfully persuaded the United Nations General Assembly to adopt the resolution requesting the advisory opinion. The government of Vanuatu successfully led a coalition of 132 nations that secured the consensus adoption of a UN General Assembly resolution calling for the advisory opinion. The resolution sought to clarify states’ legal obligations under international law to protect the climate and environment from anthropogenic greenhouse gas emissions, and to determine the legal consequences for states whose actions or omissions cause significant harm to vulnerable nations and future generations. For the first time, the world court confirmed that countries failing to mitigate or adapt adequately could face legal accountability. Although not formally legally binding, ICJ advisory opinions strongly influence states, legislation, and courts by clarifying international law and shaping emerging customary norms. For African countries, which are least accountable for emissions but most severely affected, the ruling creates both opportunities to advance claims for justice and to secure international support, as well as responsibilities to strengthen domestic climate action.

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What happens when the world’s highest court declares climate change not just a political challenge but a matter of international law? On 23 July 2025, the International Court of Justice (ICJ) issued a landmark advisory opinion that could redefine the global climate order. The momentum for this case began with a youth-led global campaign spearheaded by Pacific Islands Students Fighting Climate Change (PISFCC) and World’s Youth for Climate Justice (WYCJ). They mobilized more than 1,500 civil society groups worldwide and successfully persuaded the United Nations General Assembly to adopt the resolution requesting the advisory opinion. The government of Vanuatu successfully led a coalition of 132 nations that secured the consensus adoption of a UN General Assembly resolution calling for the advisory opinion. The resolution sought to clarify states’ legal obligations under international law to protect the climate and environment from anthropogenic greenhouse gas emissions, and to determine the legal consequences for states whose actions or omissions cause significant harm to vulnerable nations and future generations. For the first time, the world court confirmed that countries failing to mitigate or adapt adequately could face legal accountability. Although not formally legally binding, ICJ advisory opinions strongly influence states, legislation, and courts by clarifying international law and shaping emerging customary norms. For African countries, which are least accountable for emissions but most severely affected, the ruling creates both opportunities to advance claims for justice and to secure international support, as well as responsibilities to strengthen domestic climate action.

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