This week marks the first anniversary of a remarkable ruling: on 23 July 2025, the International Court of Justice (ICJ) issued an Advisory Opinion (AO) on „Obligations of States in respect of Climate Change“. Strikingly, it coincided with the ten-year anniversary of the Paris Agreement, two milestones bookending a decade in which climate ambition has lagged even as the legal case for climate action has hardened. The apex court found that states must do their utmost to protect the climate system, including through international cooperation and by regulating private actors whose activities drive emissions, and regardless of whether they are party to the UNFCCC and its Paris Agreement. Underscoring its authority, the AO was endorsed on 20 May 2026 by a UN General Assembly (UNGA) resolution initiated by Vanuatu and hailed by Secretary-General Guterres as „a victory for our planet“.

Yet the AO struggles to gain traction beyond legal and climate-justice circles, as climate policy faces mounting pushback. That is short-sighted. Multilateral institutions are needed more than ever when geopolitics is increasingly shaping global cooperation. As international cooperation remains essential to deal with global challenges, an authoritative, unanimous opinion from the world's highest court should generate leverage for global climate action, even though it is non-binding and allows states to shape their own responses.

This is where a nuanced, rather than selective, reading matters. Reception of the Advisory Opinion differs sharply, not least across the North-South fault line that is still prevalent in international climate politics. Many developed countries welcomed it chiefly for reinforcing mitigation ambition and due diligence. Many developing countries, African states not least, read it through a wider lens of development, justice and historical responsibility. For them the question was never whether climate action is necessary, but how obligations reconcile with industrialisation, energy access and poverty reduction. This reflects a legitimate concern rather than a binary of climate laggards versus leaders.

The ICJ's own separate opinions mirror this tension. Some judges argued the Court missed a historic opportunity by favouring an abstract exposition of legal principles over the central question: what legal consequences follow for states whose acts have contributed disproportionately to climate change, and for small island and least developed states that have suffered the gravest harm? Others felt the Court engaged insufficiently with the principle of common but differentiated responsibilities and respective capabilities (CBDR-RC), treating it largely as an issue of equity rather than exploring remedies such as debt relief, technology transfer or climate reparations. This matters as climate governance intersects with trade and finance, including through carbon border adjustment mechanisms, conditional finance and mounting litigation risk narrowing developing countries' policy space even as they pursue just energy transitions. Some warn of a drift from CBDR-RC towards a de facto „common but shifted responsibility“, its burden falling hardest on those least responsible.

Still, the Court demonstrates a remarkable consensus: climate obligations exist. The differences rather reflect how contested the politics of implementation remain. Moreover, it signals that the so-called Global South is no longer merely a subject of international climate law but increasingly shaping it. A Pacific youth campaign and Vanuatu's diplomacy set the AO in motion; African, Pacific and Latin American states shaped its proceedings as well as the emerging landscape of climate litigation. As the global order rapidly evolves, this agency in shaping legal and diplomatic agendas will likely grow, not recede.

For international climate cooperation, the practical implication is that the Advisory Opinion should be best understood not as a substitute for diplomacy but as a welcome addition to its toolbox. States carry both legal and political obligations, and judicial and diplomatic tracks work better as complements than alternatives. As the law becomes clearer, the more challenging task – catching up politically – now falls to states themselves.

Three things could help. First, developed countries should read the separate opinions of the justices as seriously as the headline ruling, treating genuine Southern concerns over sovereignty as legitimate, not obstructive. Second, governments should use the AO to reinvigorate, not bypass, multilateral climate diplomacy, thus driving climate action while also advancing equity and justice. Third, the newly launched South-North Commission, co-chaired by former German Chancellor Olaf Scholz and former Costa Rican President Laura Chinchilla, should prioritise the AO on its emergent agenda. Indeed, it could emerge as a high-level champion that helps to translate the AO’s authority into equitable cooperation across geopolitical divides, thereby creating a visible counterweight to unwarranted climate policy pushback. Understood holistically and taken seriously, the AO could become a catalyst for equitable international climate cooperation and as such a rare point of convergence in a fracturing world order – but only if states, not only judges, decide to make it so in spite of geopolitical power politics.

Steffen Bauer is a senior researcher in the research department “Environmental Governance” at the German Institute of Development and Sustainability (IDOS). 

Kennedy Mbeva is a research associate at the Centre for the Study of Existential Risk (CSER) at the University of Cambridge and co-convenor of the Taskforce on Climate Governance of the international Earth System Governance (ESG) Project. He is the lead author of “Africa’s Right to Development in a Climate-Constrained World”.

Reuben Makomere is a research associate at the University of Tasmania (UTAS) School of Law in Hobart, Australia and a research affiliate at the Centre for the Study of Existential Risk (CSER) at the University of Cambridge. He is a co-author of “Africa’s Right to Development in a Climate-Constrained World”.

The discussion on “what next” after 2030 has only just begun. With a bit more than four years to go, there is little official positioning on a possible successor to the 2030 Agenda right now. At the High-Level Political Forum, the central UN format for implementing the Sustainability Goals, which is taking place these days in New York, this discussion also tends to be conducted on the margins. Even the process leading to a new agenda is still unclear, as the UN Summit on the Sustainable Development Goals that is likely to sketch the way is scheduled for September 2027 under the auspices of a new UN Secretary-General. And yet, the build-up for the negotiation of a renewed or revised agenda is short. What is realistic, what is desirable for “beyond 2030”?

IDOS’ conference on “Sustainability Cooperation Beyond 2030 – Ways forward in a messy world” on 25 and 26 June in Bonn and a roundtable discussion at the Hamburg Sustainability Conference on 30 June took a leap. Both events brought together academics, senior think tank staff as well as current and former negotiators from all continents to look at what we have learnt from sustainability cooperation and the pathways towards a desired future. 

Where we are now

We can argue that the 2030 Agenda has created more momentum than was deemed possible at its inception. We have seen progress in numerous areas and countries that is not sufficiently appreciated when just observing the global average indicators. And we do have sustainability strategies in many countries, in pioneering companies and at the subnational or local level, irrespective of the national government or “political colour” of the day. There is a good track-record of reaching decision-makers at the level of sub-national entities and municipalities, where action is taken, for instance on transport, energy, or spatial planning. 

Currently, we see backsliding on the declared sustainability goals and new vulnerabilities. This is cause for concern and requires attention. National plans are not sufficient to fully implement the 2030 Agenda, as various trackers, e.g. on climate, show us. Wars have multiplied and prevent progress. Finance for development has become scarcer as countries increasingly divert resources towards military spending rather than investing in a broader understanding of security, including human, social and economic security. Additionally, demographic change in many industrialised countries results in increasing pressure on social security systems. And we are facing more extreme weather events as a result of the climate crisis. Brief: we are going through polycrises, despite a global agenda for sustainability. 

And yet, there’s value in a global agenda. One participant in Bonn invoked the unlikely reference to the Prussian military theorist Clausewitz: No strategy should be expected to be implemented as conceptualised; it always has to adapt to dynamic real-life situations. Still, strategies help to think ahead and translate aspirations into actions – and identify gaps. 

Where’s the discussion on “beyond 2030”?

It is unlikely that there is large appetite for a fully new design of the Agenda and its goals. For starters, the current agenda is already comprehensive. Moreover, renegotiating the agenda in its entirety will be challenging due to geopolitical shifts and risk assessments of supporters of a new agenda. While Europe seems much in favour of having global goals, China emphasises its orientation towards system “stability” (while likely to work on its influence), and the USA are actively advocating against the current and likely any new agenda (while sub-national entities see the need for global benchmarks). 

Participants of our recent events discussed elements for an update, e.g. the role and relevance of AI, and a circular economy, as well as renewed discussions about how to better measure wealth beyond the GDP figure. Widely shared was also that we should not only look at the “what” (the goals and indicators) but also the “how” (often referred to as the means of implementation). Yet, it sounded like broad agreement in the wish to have a vision: an agenda we should have.

What next?

The conversation on a new agenda will go through numerous rounds of exchanges of perspectives and discussions in the coming months – on substance and on how to continue. As often is the case in multilateral settings, process is likely to influence outcomes, and who to involve beyond state actors – and how – is important.

The tasks related to the 2030 Agenda obviously do not end on 31 December 2030. It is explicitly a long-term vision, “for this and future generations”. Yet, the Agenda’s legitimacy is under pressure and to simply put a new date on it won’t be sufficient. The narrative is as important as the substance. We need to come up with a positive narrative on the global commons and the global common good – and we need to tell a good story on gains through cooperation. Imaging and planning for sustainable futures is a deeply human endeavour.

The June Climate Meetings (SB64), the annual mid-year climate negotiations, delivered limited progress on several key agenda items, including the Global Goal on Adaptation (GGA). The GGA is a collective commitment by all countries under the Paris Agreement to guide adaptation efforts, strengthen accountability, and mobilise finance for vulnerable countries. While countries were expected to finalise their operational framework, longstanding political issues remained unresolved. Developing countries criticised developed countries for failing to commit to a text that would at least triple adaptation finance, as envisaged under COP 30’s Global Mutirão outcome. Without agreement on finance, negotiations made little progress.

The deadlock extends far beyond the negotiation rooms in Bonn. For climate-vulnerable countries, inadequate adaptation finance widens the gap between climate commitments and implementation. National adaptation budgets are often insufficient and must compete with other pressing development priorities. As a result, millions remain exposed to climate risks, while hard-won development gains are placed at risk. Although many developing countries already devote significant public resources to addressing climate impacts, these investments remain far below what is needed and further constrain fiscal space for other development priorities.

Recent national budget allocations in Bangladesh, one of the world’s most climate-change-vulnerable countries, help illustrate the implications of stalled progress on GGA within the national context. Bangladesh’s National Adaptation Plan of 2023 estimates that approximately USD 8.5 billion will be needed annually between 2023 and 2050 to address adaptation challenges. By contrast, Bangladesh’s national budget for 2026-2027 allocated around USD 3.19 billion for climate change adaptation. Distributed across 25 ministries, this funding supports disaster risk reduction, climate-resilient agriculture, food security, and social protection programmes. While substantial, it covers less than half of the country's estimated annual adaptation needs, underscoring that domestic resources alone are insufficient to meet adaptation goals.

The adaptation allocation, equivalent to around 4.15% of the national budget, represents an increase from previous years but also highlights fiscal trade-offs. Public investment in climate mitigation remains limited, with the FY2026–27 budget allocating only USD 814 million to renewable energy, energy efficiency, low-carbon transport, and afforestation. This falls well short of the estimated USD 1.78 billion required annually to meet Bangladesh’s renewable energy targets by 2030, including USD 553 million in public investment, while the current allocation of USD 31.1 million covers only 2.2% of this need. As a result, inadequate public financing continues to slow renewable energy deployment, while dependence on imported fossil fuels is reinforced by tax exemptions for importing them.

For countries like Bangladesh, grant-based adaptation finance is therefore essential. Without it, climate ambitions risk remaining largely rhetorical. Persistent underfunding can weaken adaptation institutions and undermine implementation efforts built over years. Yet national governments alone cannot be blamed. The war in Ukraine and the US-Iran war have heightened concerns over energy security, inflation, and economic stability, diverting fiscal resources and political attention away from climate action.

Similarly, many climate-vulnerable countries now face a dual challenge: managing escalating climate risks while navigating an increasingly uncertain geopolitical landscape. Energy insecurity, supply-chain disruptions, and economic volatility have been added to an already long list of climate-related threats, including sea-level rise, floods, droughts, salinity intrusion, food insecurity, displacement, and ecosystem degradation.

The lack of progress on the GGA at SB64 is therefore deeply concerning. Climate-vulnerable countries need continuous and adequate finance to implement adaptation measures and meet their climate commitments. Yet the political and fiscal space for adaptation is shrinking, not because climate risks have diminished, but because competing crises increasingly dominate national and international agendas. COP31 must restore momentum by agreeing on an operational GGA that is measurable, finance-responsive, and implementation-oriented. This requires agreed adaptation indicators, stronger accountability, and predictable grant-based finance that enables vulnerable countries to implement their adaptation priorities.

A B M Hasanuzzaman is a 2025 Alexander von Humboldt International Climate Protection Fellow hosted by IDOS.

Dr Aparajita Banerjee is a sociologist and Senior Researcher in the research department “Environmental Governance” at the German Institute of Development and Sustainability (IDOS).