Mayors step up on climate action at COP31, as banks and builders back them

In this edition: the number of cities signing up to deliver a year of climate action rises by 60%; subnational development banks channel climate finance to city resilience; and the number of European companies reporting progress on building emissions increases nearly fivefold.

Cities are delivering resilience, climate finance, and emissions cuts

It’s “Resilient Cities and Built Environment” day at COP31 and the headlines are coming from mayors, subnational development banks and building councils.

Earlier this year we covered the cities tackling brutal summer heatwaves through an Action Agenda plan to green cities to beat the heat. That includes Lagos, Nigeria, which is redesigning its infrastructure from cool-roofed public buildings to shaded transit hubs and solar-powered electric ferries, as temperatures surge towards 46°C.

Cities are racing against the clock to prepare for escalating climate impacts, even as they face a yearly USD 4.5–5.4 trillion funding gap for climate-resilient infrastructure.

That’s where the Action Agenda comes in with plans to help close the financing gap, cut building emissions, and improve resilience.

Which brings us to the city leaders, subnational development banks, and building councils delivering the top headlines from today:

Sixty-nine cities plan their next year of climate action

Last year at COP30, 42 cities signed up to a “Yearly Offer of Action”. The idea was to get cities to commit to concrete climate action over 12 months, such as tackling El Niño flood risks or planting mangroves to protect vulnerable coastal communities.

A year later, the results are in. In Freetown, Sierra Leone, 27,000 households have been connected to private waste collection through the city’s #DortiMusGo initiative, while Melbourne, Australia, has created 6,000 m² of additional green spaces.

Now, at COP31, 69 mayors have signed up for the “Yearly Offer of Action” for 2027 – a 60% increase from last year. Those mayors represent more than a quarter of a billion people. Projects range from flood warning systems in Addis Ababa to London’s first dedicated heat plan. A building-efficiency incentive in Melbourne will target 400 commercial buildings in its first year, and is anticipated to cut more than 4,400 tonnes of emissions over ten years.

It’s all part of progress made through the Action Agenda’s multilevel implementation plan.

Development banks are helping cities get their hands on climate finance

Local governments may know which roads need upgrading or where flooding is worst, but turning those priorities into projects that qualify for investment is another matter. Subnational development banks are beginning to bridge that divide, again under the Action Agenda's multilevel implementation plan and the Coalition for High Ambition Multilevel Partnerships (CHAMP).

Already this year, the Global Alliance of Subnational Development Banks has disbursed USD 308 million in urban climate finance. In Senegal, it paid for flood and stormwater work and for moving families away from eroding coastline. In Colombia, funds went to energy efficiency, drinking water and river clean-up.

Meanwhile, a European Union-supported pilot called “Finance Your Cities” is helping the Global Fund for Cities Development (FMDV) channel finance to the local level through a new generation of multilevel Country Platforms. Cameroon’s subnational bank FEICOM has verified 23 projects on flood management and reforestation worth USD 11 million. Another 30 projects are awaiting verification in the coming months. A dedicated climate finance line is being negotiated with the EU, and the money is expected to start flowing in 2027. In Madagascar, nine major cities have built a USD 35 million pipeline for waste, sanitation, and road projects. “Finance Your Cities” is also in talks to scale to 14 more countries across Africa.

Separately, in Brazil, development finance is helping cities tackle another major source of emissions: public transport. Through the Brazil Mutirão Program, a partnership involving C40 Cities, the Global Covenant of Mayors for Climate & Energy and Bloomberg Philanthropies, procurement has been formalized for more than 200 electric buses. A further pipeline of nearly 600 buses is in development.

Climate finance is new territory for many of these banks. The large multilateral development banks have only been at it for about a decade themselves. But through the Action Agenda, subnational banks are looking to scale up fast.

Companies reporting real progress on building carbon up nearly fivefold in a year

The buildings and construction sector produces 37% of global CO₂ emissions. The construction decisions being made now will shape that footprint for decades. In Africa and Asia-Pacific, much of the building stock expected to exist in 2050 has yet to be built. That creates an opportunity to avoid locking in inefficient buildings and costly retrofits as cities grow.

The COP31 Presidency is targeting a reduction in operational energy intensity for global building stock by 25% by 2035 under its Antalya Compact for Energy Efficient Buildings, and in line with its ‘35x35’ electrification goal. Action Agenda partners are working to improve building efficiency through multiple plans to accelerate decarbonization, net-zero emissions, and resilience roadmaps for building and construction.

For example, the World Green Building Council (WorldGBC) and its network of national Green Building Councils are advancing decarbonization and resilience roadmaps – showing how national and subnational governments can deliver climate action through building codes, performance standards, clean heating and electrification, and finance.

In Europe, WorldGBC’s #BuildingLife programme reports that more than 970 companies have now endorsed national roadmaps, up 20% since 2024. The number reporting progress on cutting building emissions has risen nearly fivefold in a year, to more than 300. Cities from Helsinki to Milan are writing carbon limits into their building codes. Spain is moving to write life-cycle carbon into its building codes as every EU member state has to set carbon limits for new buildings from 2030.

Now, with USD 5.5 million in new funding since COP30, WorldGBC will expand its decarbonization roadmaps to 19 countries, with China, Ethiopia, Nigeria and South Africa next on the list.

WorldGBC says roadmaps are just the start. But clear rules give companies the confidence to invest, and their achievements give governments the confidence to set tougher standards.

In other news

• Ports now have a common way to measure how well they would stand up to climate shocks. The Resilience4Ports indicators, launching today at COP31, are a self-assessment tool that helps a port find its weak spots, decide where to invest and track progress over time. They score a port across five areas: assets and operations, governance, finance, people and communities, and coastal and marine ecosystems. Climate disruption already puts an average of USD 122 billion of economic activity at risk each year across 1,320 ports. The indicators were tested at five ports before launch. One of them, Kuantan Port in Malaysia, says applying them confirmed the case for a rail link across the peninsula that would let cargo skip the Strait of Malacca, which is only about 3 km wide at its narrowest and prone to congestion.

• A year after COP30, the Action Agenda Plan to Accelerate Resilient and Adaptive Transport Infrastructure has published its first major global report. It brings together 100 solutions from more than 90 organizations in 46 countries, covering roads, railways, ports, airports and multimodal systems. By contributors’ own figures, the featured case studies have strengthened the resilience of more than 34 million people and 436 million journeys a year. The next step is to help governments incorporate transport into their National Adaptation Plans, with the initiative running through to the 2028 Global Stocktake. Read the report.

For media enquiries, please contact: christineluby@climatechampions.team and guilhermelarsen@climatechampions.team.