The past years have been pivotal for international climate advocacy. In 2024, the International Tribunal for the Law of the Sea (ITLOS) promulgated the Advisory Opinion on Climate Change and International Law, which defined the duties of States under the UNCLOS in relation to climate change. This was followed by the Inter-American Court of Human Rights (IACtHR), the regional court of the Organization of American States, with its promulgation of the Advisory Opinion on Climate Emergency and Human Rights on 29 May 2025. This advisory opinion, although issued by a regional organization, pushed the momentum forward by holding that the right to a healthy climate is a human right and by clarifying the binding obligations to prevent irreversible harm to the environment. 

It is not a surprise that the promulgation of the long-awaited Advisory Opinion on the Obligations of States in Respect of Climate Change of the International Court of Justice (ICJ AO), passed a year ago on 23 July 2025, was warmly received and celebrated. Though the nature of the AO is non-binding, it was seen as creating leverage points for accelerating climate action. It would now be beneficial to assess the effects of the ICJ AO, one year later. 

In the international law landscape, one of the most significant consequences of the ICJ AO is the passage of a UN General Assembly Resolution (UNGA Resolution) recognizing the AO in the UN’s 80th Session. The UNGA Resolution welcomes the AO, which was borne out of a similar Resolution passed in 2023 requesting the ICJ for an advisory opinion on the obligations of States in respect of climate change. 

The UNGA Resolution was prepared by a Core Group led by Vanuatu, the State which also spearheaded the diplomatic campaign for the ICJ AO, and was joined by the Philippines. This cross-regional coalition negotiated the text of the UNGA Resolution which was later brought before the General Assembly. The discussions at the level of the General Assembly were contentious. Tensions arose when a group of States, led by petrostates Saudi Arabia and Kuwait, tabled amendments which modified language of the text, making it weaker. Nonetheless, the UNGA Resolution was passed on 13 May 2026 with 141 votes in favour and 8 against, and 28 abstentions.

 The UNGA Resolution not only reaffirmed the key findings of the ICJ AO, but translates these into actionable language. It called upon States to comply with obligations under international law, and specifically emphasized the stringent standard of due diligence for preventing significant harm to the climate system (ICJ AO par 347), cooperation in good faith to prevent significant harm to the environment (ICJ AO par 218, 238) and the protection of the climate system and the environment as preconditions for the full enjoyment of human rights (ICJ AO par 403). Issues which are existential to States were also reiterated. The UNGA Resolution stated that a State would not necessarily lose statehood if one of its constituent elements would disappear (ICJ AO par 363). Notably, the UNGA Resolution also asserted the collective temperature goal of holding the increase in the global average temperature to 1.5 degrees Celsius above pre-industrial levels (ICJ AO par 223) and it noted that a breach of any of the obligations identified by the ICJ constitutes an internationally wrongful act entailing the responsibility of that State (UNGA Resolution par 9).

The most essential portion of the UNGA Resolution are the last two paragraphs, which mandate actions on the part of the General Assembly. Paragraph 10 mandates the preparation of a report containing ways to advance compliance with all obligations in relation to the Court’s findings, to be presented at the 82nd Session in September 2027. Paragraph 11 instructs the inclusion of an item entitled “Follow-up to the advisory opinion of the International Court of Justice on the obligations of States in respect of climate change” to the provisional agenda of the 83rd Session in September 2028.

In the domestic context, the ICJ AO has already started to affect climate policy. As the host country for the Board of the Fund for Responding to Loss and Damage, Philippine officials, including President Ferdinand Marcos Jr., have constantly emphasized cooperation among States and the need for climate finance. Former DENR Secretary Lotilla welcomed the ICJ AO as it “affirms the legal obligation of States to address climate change and vulnerable ecosystems.” The push for stronger climate finance was felt as the Philippine delegation to 64th Sessions of the UNFCCC Subsidiary Bodies in Bonn, Germany expressed serious concern about the increasingly unpredictable state of climate finance. 

Notably, there is the pending House Resolution No. 1074 introduced by Deputy Speaker David Suarez and Rep. Ma. Cristina Lopez, filed in June 2026, which recognizes the advisory opinions relating to climate change issued by the ICJ and ITLOS. The Resolution acknowledged that the climate obligations under the treaties mentioned in the AOs constitute binding international legal commitments, which are consistent with the Philippine Constitution. The Resolution further urges the Executive Department to reflect the ICJ and ITLOS AOs in climate policy and UNCLOS-based advocacy. It also called on the Executive Department to strengthen and progressively enhance the Philippines’ NDC. The Supreme Court was also called to consider guidelines and annotations to the Rules of Procedure for Environmental Cases in order to accommodate the ICJ and ITLOS AOs.

While it is clear that the full effects of the ICJ AO are yet to fully materialize, the path forward looks hopeful. As stated in paragraph 456 of the ICJ AO: “a lasting and satisfactory solution requires human will and wisdom — at the individual, social and political levels — to change our habits, comforts and current way of life in order to secure a future for ourselves and those who are yet to come.” The Court no doubt calls upon intergenerational responsibility, a concept the Philippines has long recognized and embraced.