The spirit of mutirão — communities joining forces to get something done — runs deep in Brazil’s culture. Here at COP30 it is inescapable. The phrase is on the lips of negotiators from nearly 200 countries and it has become the defining ethos of this conference: global climate cooperation built on shared effort and mutual accountability. 

National governments and cities, campaigners and businesses must now come together in that same spirit to move from the age of negotiation to the decade of delivery.

Here in Belém it is impossible to forget why this matters. Every country has its story of floods, heatwaves, wildfires or supercharged storms that strike hardest in the places least able to cope. At both the Brazilian Ministry of Cities and C40 Cities we see every day that adapting to current challenges and turning the tide on the climate crisis are not separate challenges but part of one mission: to protect the people and places we love now and for generations to come.

We are becoming a planet of urbanites, even here in the Amazon rainforest there are nearly 22 million people living in cities like Belém, so it’s crucial to combine preservation with sustainable and inclusive development for those communities. Across Brazil and around the world, cities are already facing up to this challenge. They are greening streets, serving sustainable and nutritious lunches to school children, keeping the most vulnerable safe from heat and floods, designing urban areas that meet the needs of people — not cars — and creating good green jobs for all. 

Every country has its story of floods, heatwaves, wildfires or supercharged storms that strike hardest in the places least able to cope.

Last week we both joined mayors, governors and regional leaders representing more than 14,000 cities, towns, states and provinces at the Bloomberg COP30 Local Leaders Forum in Rio de Janeiro. It was the largest and most diverse gathering of subnational climate leaders in history, and it sent an unmistakable message to national governments: local leadership is already delivering and it is ready to go further. 

Following this historic moment and boosted by the COP30 presidency’s willingness to put urban climate action to the fore, cities came to COP30 with three clear offers:

1. Partner with us to implement national climate plans and turn strategies into results that improve lives.
2. Invest in the local project pipeline. More than 2,500 projects seek support and thousands more can follow if the political will is forthcoming.
3. Make COP a place of action and accountability where progress is measured not in pledges but in cleaner air, reduced health risks and green jobs created. 

If countries accept these offers the COP process itself can evolve from negotiation to delivery, from promises to proof that the Paris Agreement goals can be not just agreed but also delivered. 

This is not just a theory. It is already happening here. Under President Luiz Inácio Lula da Silva’s leadership Brazil has embedded ‘climate federalism’ into national policy, linking the federal government, states and municipalities in coordinated delivery for the good of all Brazilians and the planet.  

Research shows that, in countries that are part of the Coalition for High Ambition Multilevel Partnerships for Climate Action (CHAMP), collaboration between national and subnational governments could close 37 percent of the global emissions gap needed to stay on a Paris-aligned pathway. Launched at COP28, CHAMP already includes 77 nations and continues to grow. Brazil is showing what this looks like in practice and is inspiring more countries to take action. 

On the city side of the equation the evidence is unequivocal. Per-capita emissions in C40 Cities are falling five times faster than the global average and more than 70 percent of C40 cities have already peaked emissions and are now delivering significant emissions reductions. Many C40 cities are also committing to a Yearly Offer of Action, demonstrating how to translate global ambition into measurable progress by announcing every year what they will do in the next 12 months to accelerate climate action. 

To unlock that progress the financial system must evolve too. The world’s development and climate finance architecture was designed for national ministries not city halls. Yet cities control or influence most of the decisions that shape emissions from transport, waste, buildings and land use. This means they can enhance and accelerate the implementation of National Climate Plans. Much more could be achieved if urban climate finance is increased and local governments have direct access to the capital they need.

The Baku to Belém Roadmap is calling for $1.3 trillion of annual climate investment to support developing countries. This could help scale-up finance and make it more reliable and accessible while prioritizing a just and resilient transition. Cities have the projects, partners and are the closest level of government to people’s daily needs — enhanced collaboration, preparation and direct access to finance can help bring their ambitious visions to life.    

To unlock that progress the financial system must evolve too. The world’s development and climate finance architecture was designed for national ministries not city halls.

We have both witnessed here in Brazil how quickly change accelerates when local and national leaders come together. When buses run on clean power, when families in flood-prone neighborhoods move into resilient homes, when air is cleaner and streets are safer, climate policy stops being abstract. It becomes tangible progress that citizens can see and support. 

If COP30 becomes the moment the world embraces climate federalism and genuine national and sub-national collaboration, then Brazil will have set a new global standard for collective climate delivery and a real just transition. 

The decade of delivery begins here in Belém. Let us build it together, in mutirão.