- Crucial talks begin with city climate action serving as an inspiration to national negotiators
- COP30 Presidency and UN endorse cities as critical to the coming ‘decade of delivery’
- COP30 Local Leaders Forum and World Mayors Summit in Rio demonstrates the vital importance of climate leadership from cities and regions around the world
- Local Leaders Forum Joint Statement delivered to UN Secretary General António Guterres at COP30 World Leaders Summit
Belém, Brazil (10 November 2025) – C40 Cities’ COP delegation has travelled to Belém buoyed by a ringing endorsement of city climate leadership from both the COP30 Presidency and the United Nations.
Last week the C40 World Mayors Summit 2025, part of the COP30 Presidency and Bloomberg Philanthropies Local Leaders Forum, brought together nearly 300 sub-national leaders from five continents. Over three days in Rio they reaffirmed their commitment to protect their residents from the dangers of the climate emergency whilst also delivering climate solutions that improve livelihoods, create fairer societies and boost local economies.
The essential role of cities in tackling the climate emergency was endorsed by the Brazilian COP30 Presidency and echoed by UN Special Adviser and Assistant Secretary General for Climate Change Selwin Hart, who pledged to push for “the formal recognition of cities within [the] global climate process.”
As mayors arrive into Belém they will continue to put forward their Yearly Offers of Action, their intention to set out climate actions every year ahead of future COPs until climate breakdown is under control. From low-emission zones to renewable energy, sustainable transport to urban redesign, C40 cities are showing what real on-the-ground delivery looks like.
In the Local Leaders Joint Statement, supported by more than 14,000 cities, towns, states, regions, and provinces and delivered to UN Secretary General António Guterres at the COP30 World Leaders Summit, cities and subnationals declared: ‘To the world leaders gathering in Belém: you can count on us. Local leaders are ready to join you in a true global mutirão—working side by side to turn ambition into action and promises into progress. Our collective commitment will help advance the COP30 Action Agenda and fuel the spirit of global collaboration needed to deliver a just, resilient, and sustainable net-zero future for all not only for this COP, but for generations to come.’
Now that work continues in Belém. C40 Cities approach COP30 with three key calls to support the COP30 Presidency’s call to move from negotiation to implementation:
- The COP30 outcome texts to officially recognise cities and subnational governments as full partners . Only then can we bridge the implementation gap, deliver on the Paris Agreement, and secure a just transition.
- COP negotiators to build on the success of CHAMP and create a space inside the COP process to focus on action and tangible solutions through multi-level partnerships and collaboration between subnational and national, such as a Work Program, and next steps on the Just Transition outcomes that include cities as just transition implementers.
- COP30 outcomes to call for more funding for urban climate action. The mobilisation of public and private finance is needed for climate adaptation, infrastructure and the just transition, especially in emerging and developing economies. The Baku to Belém Roadmap sends encouraging signals on these priorities, but cities must be at the table as the Roadmap is operationalised.
C40 Cities and the Global Covenant of Mayors (GCOM) will be represented on the ground in Belém by the mayors of Paris, Adelaide, Savannah, Onkaparinga, Fortaleza and Renca with further representation from Austin, Manheim, Montreal, Sao Paulo, Singapore and Rio de Janeiro.
This year’s COP is an unparalleled opportunity to champion city climate delivery, advance the Yearly Offer of Action, and secure greater subnational inclusion.. Mayors believe we can overcome fear with hope, unity, and action and demonstrate that subnational leadership is the essential for climate solutions, a just transition and disarming disinformation
This unified approach embodies the ‘Mutirão’ spirit of collaboration called for by the COP30 Presidency: establishing a front where cities, national governments, workers, businesses, youth, and civil society collaborate to deliver on the Paris Agreement and accelerate action on the ground.
By strengthening this multilateral system and rooting our work in justice, we can collectively secure a cleaner, greener, and fairer future for all, driving the unstoppable action that the urgency of the crisis demands.
C40 Co-Chair and Mayor of London, Sir Sadiq Khan said: “At the C40 World Mayors Summit we felt a collective surge of energy, enthusiasm and determination as over 300 cities committed to working together to create a fairer, safer and greener future for everyone.
“Now cities are taking that message to COP30. From London to Lagos; Barcelona to Bogota, it’s cities that are stepping up. Cities have proved what can be achieved when action is taken, it is time for the world to follow our lead.”
C40 Co-Chair and Mayor of Freetown, Yvonne Aki-Sawyerr OBE said: “COP30 presents the best opportunity in a decade for meaningful climate progress on the international scale but this will only be possible if cities are at the center of both formulating and implementing the next steps.
“Our cities are growing, by 2050 the urban population of Africa will have doubled, and they are young: it is estimated that 60% of people living in cities will be under the age of 18 by 2030.
“These young people deserve to live in clean, safe, prosperous cities, and this will only be possible if our generation takes action now. To do this we need support, including access to finance and recognition at the highest levels, starting at COP30.”
C40 Cities Executive Director Mark Watts said: “Over the last twenty years C40 Cities have proven unequivocally that local climate leadership works: 73% of our cities, for which data is available, have already peaked their emissions, and three questers are now cutting them faster than their national governments.
“The C40 World Mayors Summit showcased the incredible momentum and collective commitment of subnational leaders to deliver the Global Mutirão. Our focus is now on Belém and the ‘decade of delivery’: mayors will be there to showcase the action they are taking every year.
“COP30 must recognize cities as indispensable partners in securing a just transition and implementing the Paris Agreement. But recognition isn’t enough; finance must follow. We urge global leaders to unlock the funding cities urgently need, especially in the Global South, to scale up our proven, people-centered solutions.”