We join the broader world in welcoming the International Court of Justice (ICJ) ruling that states are obliged, under international law, to tackle climate change, and failing to do so could leave them open to being sued.

The ICJ, which had been asked to determine what obligations countries were under to curb planet-heating emissions and to lay out possible consequences for failing to do so, issued its ruling last week.

The court correctly described climate change as an “urgent and existential threat” and declared that countries breaching their climate obligations were committing a “wrongful act”.

Among the key points in the ICJ ruling is that countries have binding legal obligations under the United Nations (UN) climate negotiations framework, as well as in customary law, to produce climate plans that represent the framework’s “highest possible ambition”.

The court said that all climate plans taken together should be “capable of achieving the temperature goal of limiting global warming to 1.5 degrees Celsius above pre-industrial levels”.

“Non-compliance with emission reduction commitments by a State may constitute an internationally wrongful act,” the ICJ said.

Just as important, the court stated in its advisory opinion that climate impacts, like sea-level rise, drought, desertification, and weather disasters “may significantly impair the enjoyment of certain human rights, including the right to life”.

Additionally, the ICJ ruled that any State that fails to take appropriate action to protect the climate system from greenhouse gas emissions, including through fossil fuel production, fossil fuel consumption, the granting of fossil fuel exploration licences, or the provision of fossil fuel subsidies may constitute an internationally wrongful act which is attributable to that State.

The ruling has been hailed as an important moment in the fight for accountability from the nations deemed most responsible for global warming due to their carbon footprints.

Germany described the ruling as an “important milestone”; the European Union (EU) agreed and said it “confirms the immensity of the challenge” the world faces, “and the importance of climate action and the (2015) Paris Agreement”.

European Commission spokeswoman Ms Anna-Kaisa Itkonen told journalists that the ruling “reaffirms the need of taking collective and ambitious action”, while China’s Foreign Ministry spokesman Mr Guo Jiakun said, “The advisory opinion reflects the long-term positions and propositions of the vast majority of developing countries… and has positive significance for maintaining and promoting international climate cooperation.”

The advisory opinion is not legally binding but carries political and legal weight. The challenge for the international community now is to get full commitment to the UN’s climate treaties and mechanisms.

That will not be easy, because so far major polluting countries have failed to implement measures that would contribute to meeting the Paris Agreement of limiting global warming to 1.5 degrees Celsius.

Last October, just ahead of the COP29 climate summit, UN Secretary General Antonio Guterres said humanity is “paying a terrible price” for inaction on global warming as time was running out to avoid climate disaster.

At the time, the UN Environment Programme argued in its Emissions Gap report that the next decade is critical in the fight against climate change as the current trend would result in a catastrophic 3.1 degrees Celsius of warming this century.

Mr Guterres’ warning last October is even more relevant today: “Either leaders bridge the emissions gap, or we plunge headlong into climate disaster, with the poorest and most vulnerable suffering the most.”