Host Brazil will preside and set the agenda. For the talks to be a success, world leaders need to beef up efforts and money for adapting to climate change and fund billion-dollar efforts to prevent deforestation and land degradation, said Suely Vaz, who used to run Brazil’s environment agency.

After a year of talks, COP30 host Brazil on Wednesday laid out a plan to scale climate finance to $1.3 trillion a year and faced several early signs of the testing political backdrop as the Amazonian city of Belem prepares to welcome world leaders.

World leaders meet Thursday in the Brazilian Amazon in an effort to show that climate change remains a top global priority despite broken promises and the United States shunning the gathering. About 50 heads of state and government are expected in the rainforest city of Belem for a summit on Thursday and Friday ahead of the annual UN Conference of Parties (COP) climate negotiations that open next week.

Money, climate commitments and the role of America are set to feature highly during the two-week long climate talks starting on Nov 10 in the Amazon rainforest.

The summit was organized by C40, a network of mayors from big cities that has pushed to be included in decisions on how to combat global warming and adapt to its effects.

From Nov. 10-21, 2025, world leaders, scientists, policymakers, industry representatives and delegates from around the globe will gather in the Amazon city of Belém, Brazil at the 30th United Nations (UN) Conference of the Parties,