Rio will host the World Summit of C40 Mayors

Between November 3 and 5, 2025, Rio de Janeiro will be the stage of the C40 World Summit of Mayors, the largest international meeting of cities committed to climate action. The event precedes COP30, which will take place in Belém from November 10.

The summit, which takes place every three years, will gather in Rio mayors from over 100 major cities, as well as global climate leaders, investors, philanthropists, private sector representatives, international organizations and members of civil society.

The announcement was made on Tuesday (24), during the London Climate Action Week, by the mayor Eduardo Paes, next to Sadiq Khan, mayor of London and co-president of the C40.

The meeting will officially mark the opening of the COP30 Local Leaders Forum in Rio, organised by Bloomberg Philanthropies and the COP30 Presidency. The event will serve as preparation for the United Nations Climate Conference, which takes place days later in Bethlehem.

In addition, the Summit will celebrate the 20 years of the creation of the C40 network, founded in 2005, and will present priorities for the next 12-month cycle. The main objective is to maintain the pace of climate action and ensure adequate resources for cities to face current environmental challenges.

The Forum will focus on strengthening multilateralism and diplomacy between different spheres of government, in order to accelerate the implementation of the Paris Agreement, promoting greater cooperation between local and national leaders to meet the UN climate targets.

One of the central themes will be climate finance, with emphasis on the need to unlock resources that allow mayors and governors to expand their communities' adaptability and resilience.

The program of the COP30 Local Leaders Forum, from 3 to 5 November in Rio, was also released on Tuesday. The agenda includes:

World Summit of C40 Mayors - Celebrating the 20 years of network creation, the event will be conducted by Sadiq Khan and hosted by Eduardo Paes. It will bring together global mayors, including the FNP and the Global Covenant of Mayors, with debates on energy, mobility, infrastructure, decarbonization of buildings, solutions based on Brazilian urban nature and innovation.

Global Summit of States and Regions – Organized by the Under2 Coalition, it will gather governors and regional leaders to present climate actions in renewable energy, transportation, industry and land use.

Local Leaders Award Ceremony – Organized by C40 and the City of Rio, the event will award two subnational governments - one Brazilian and one international - for climate projects, in topics such as fair energy transition, adaptation, health and multilevel partnerships.

High-Level Political Dialogue of CHAMP – In partnership with the World Resources Institute, the C40 and Global Covenant of Mayors, the meeting will strengthen multilevel collaboration and present the commitments of CHAMP - the acronym for "High Ambition Multilevel Partnerships for Climate Action", - an initiative to promote cooperation between national and subnational governments in combating climate change through partnerships.

America Is All In Exchange – In partnership with the U.S. Climate Alliance, Climate Mayors and others, the conference focuses on highlighting the local climate leadership of US cities and their advances.

After the closure of the program in Rio, on November 5, a delegation of mayors and local authorities will proceed to Belém, taking the proposals discussed in the Rio capital to COP30.