The UN’s COP30 climate summit takes place in the “most complex geopolitical context” yet, the Brazilian hosts have warned as the country grapples with driving action to tackle rising temperatures just weeks after US President Donald Trump called climate change a “con job”.

Unlike many of the recent UN climate talks, where a single big topic dominated — such as finance at COP29 in Baku and the transition away from fossil fuels at COP28 in Dubai — several issues are up for debate at this year’s summit in the Amazonian port city of Belém. 

But difficult geopolitics — especially as Trump piles pressure on countries around the world to roll back climate efforts — have overshadowed much of the preparations and raised questions about how much progress can be made as leaders from almost 200 countries meet to negotiate global climate action.