From 8 to 18 June 2026, delegates from across the globe are convening in Bonn, Germany, for the 64th sessions of the Subsidiary Bodies of the United Nations Framework Convention on Climate Change (UNFCCC), commonly referred to as SB64. The Bonn Climate Conference represents a pivotal milestone in international climate governance, serving as an intermediate negotiating session between COP30 and COP31, which is scheduled to take place in Antalya, Türkiye, in November 2026.
COP30, held in Belém, Brazil, delivered progress across several strategic areas of the climate agenda, including adaptation, the Global Stocktake, the Just Transition Mechanism, Loss and Damage, Article 6 on carbon market mechanisms, and the Gender Action Plan. The conference also launched two voluntary initiatives (the Global Implementation Accelerator and the Belém Mission to 1.5°C) to accelerate climate action and strengthen implementation efforts.
However, negotiators were unable to reach an agreement on a formal roadmap for the phase-out of fossil fuels, and made only limited progress in strengthening Nationally Determined Contributions (NDCs), leaving important mitigation challenges unresolved.
As the midpoint between two Conferences of the Parties, SB64 is expected to focus primarily on translating previous political commitments into practical implementation frameworks and operational measures.
One of the central discussions in Bonn will concern the future of the Mitigation Work Programme, a central mechanism for advancing global emission reductions and strengthening international mitigation efforts. The issue has become increasingly prominent following the failure to incorporate a fossil fuel phase-out roadmap into the final COP30 decisions.
Delegates will also continue technical negotiations on the Global Goal on Adaptation (GGA), including the implementation of the fifty voluntary indicators adopted at COP30 to assess progress in climate adaptation. Discussions are expected to focus on methodological approaches, integration into national adaptation planning processes, and linkages with climate finance mechanisms.
Climate finance remains among the most politically sensitive issues on the Bonn agenda. COP30 established a two-year work programme under the framework of the New Collective Quantified Goal (NCQG), including efforts to triple adaptation finance by 2035.
Nevertheless, significant differences persist between developed and developing countries.
Developing countries continue to argue that meaningful progress on mitigation, adaptation, resilience, and loss and damage cannot be achieved without substantially increased financial support from wealthier nations.
The Bonn conference will therefore mark the formal launch of the climate finance work programme agreed in Belém.
Another important objective of the Bonn negotiations will be to prepare the groundwork for the second Global Stocktake, scheduled for completion in 2028. Delegates will begin discussions on how future assessment processes can remain science-based, transparent, inclusive, and accessible, in accordance with IPCC findings, the Paris Agreement framework, and countries’ economic, social, and geographical differences.
Another central theme of SB64 will be climate justice. COP30 established the Just Transition Mechanism, reflecting growing recognition that climate action must address social inequalities and broader economic transformation alongside environmental objectives.
At SB64, negotiators will begin discussions on operationalising the mechanism, although important questions concerning governance, investments and implementation remain unresolved.
Ensuring that climate policies remain equitable, inclusive, and socially sustainable is one of the defining challenges of contemporary climate governance.
In this context, it is important to highlight a major recent development in international climate law that could influence future climate policy, governance, and public debate.
On 20 May 2026, the United Nations General Assembly adopted a landmark resolution endorsing an advisory opinion issued by the International Court of Justice (ICJ) concerning states’ legal obligations to address climate change.
The resolution was approved by an overwhelming majority, receiving 141 votes in favour, 8 votes against, and 28 abstentions. The countries voting against were Belarus, Iran, Israel, Liberia, Russia, Saudi Arabia, the United States, and Yemen.
The vote followed the historic advisory opinion delivered by the ICJ in July 2025.
In its advisory opinion, the Court concluded that, under existing international law, actions contributing to climate change may constitute unlawful conduct and that states have obligations to prevent significant environmental harm and cooperate in protecting vulnerable populations. Importantly, the judges determined that these responsibilities extend to activities associated with greenhouse gas emissions, including fossil fuel extraction and consumption, as well as government subsidies supporting fossil fuel industries.
The case originated from an initiative led by Vanuatu, a Pacific island nation particularly vulnerable to climate change impacts, and supported by law students from Pacific Island nations facing existential threats from sea-level rise. Although ICJ advisory opinions are not legally binding, they carry substantial legal and normative authority and frequently influence future legal interpretations, public policy development, and judicial decisions.
The Court further stated that states that fail to meet their obligations may bear legal responsibility for climate-related harm and may be required to cease harmful activities, provide guarantees of non-repetition, and offer reparations where appropriate.
The General Assembly resolution emphasises that all UN member states should take all possible measures to avoid causing significant harm to the climate system and the environment, including reducing emissions and fulfilling commitments under the Paris Agreement. It also highlights the protection of fundamental human rights, including the rights to life, health, and an adequate standard of living.
UN Secretary-General António Guterres welcomed the resolution, describing it as a powerful affirmation of international law, climate justice, and scientific evidence. He emphasised that those least responsible for climate change often experience its most severe consequences and argued that climate justice requires a rapid and equitable transition away from fossil fuels towards renewable energy systems.
The legal momentum generated by the ICJ advisory opinion arrives at a particularly significant moment for international climate diplomacy.
Together, the General Assembly resolution and the Bonn Climate Conference illustrate an increasing convergence between climate governance and international law.
The United Nations General Assembly’s endorsement of the International Court of Justice’s advisory opinion strengthens the legal basis for holding states accountable for their climate policies and inaction in protecting the environment. Climate justice is now emerging as a central pillar of international climate discussions.
The SB64 negotiations are expected to focus less on new commitments and more on implementing existing obligations. Although SB64 is an intermediate negotiating session, its outcomes will significantly influence preparations for COP31 in Antalya and the second Global Stocktake in 2028. Mitigation, adaptation, climate finance, and justice will be the main topics of discussion.
Progress on Mitigation, adaptation, climate finance, and climate justice will be at the center of discussions. Bonn is expected to host critical discussions on climate finance, helping to rebuild trust after COP30 and laying the foundation for more ambitious outcomes at COP31.
As countries move beyond announcing new climate commitments, increasing attention is being placed on implementation, transparency, and measurable progress. The period leading up to COP31 will be crucial for demonstrating whether existing pledges can translate into tangible outcomes, strengthening confidence in the multilateral climate process and informing future negotiations.