With China leading the way by announcing its first emission cuts, world leaders have said they are getting more serious about fighting climate change and the deadly extreme weather that comes with it.

At the United Nations high-level climate summit on Wednesday (September 24, 2025), Chinese President Xi Jinping announced that the world's largest carbon-polluting country would aim to cut emissions by 7-10% by 2035. China spews more than 31% of the world's carbon dioxide emissions, and they have long been soaring.

The announcement came as more than 100 world leaders gathered to talk of increased urgency and the need for stronger efforts to curb the spewing of heat-trapping gases.

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With major international climate negotiations in Brazil six and a half weeks away, the United Nations Secretary-General Antonio Guterres convened a special leaders summit on Wednesday (September 24, 2025) during the General Assembly to focus on specific plans to curb emissions from coal, oil and natural gas.

In a video address, Mr. Xi pledged that China would increase its wind and solar power six-fold from 2020 levels, make pollution-free vehicles mainstream and "basically establish a climate adaptive society."

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Europe then followed with a less detailed and not quite official new climate change fighting plan. Ursula von der Leyen, president of the European Commission, said their infrastructure and investment in renewable energy and the price of carbon had all increased, and their emissions are down nearly 40% since 1940.

"Last week, member states agreed that their nationally determined contribution would range between 66% and 72%, and that they would formally submit their plan before the November negotiations," she said.

Mr. Xi and Brazil's leader also took thinly veiled swipes on Wednesday (September 24, 2025) afternoon at U.S. President Donald Trump's attacks a day earlier on renewable energy and the concept of climate change. "While some country is acting against it, the international community should stay focussed on the right direction," Mr. Xi said.

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Brazilian President Luiz Inácio Lula da Silva, who is hosting the upcoming climate conference, said, "No one is safe from the effect of climate change. Walls at borders will not stop droughts or storms," Mr. Lula said. "Nature does not bow down to bombs or warships. No country stands above another. All of us may lose because denialism may actually win," he concluded.

Mr. Guterres said, "The science demands action. The law commands it. The economics compel it. And people are calling for it." Marshall Islands President Hilda Heine said she was there to issue "a demand for us all to wake up from a community whose hospitals and schools are being destroyed" by rising tides. She said she has regularly been awakened by floods and drought emergencies in her small island nation and that it will soon be others' turn.

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"If we fail to wake up now and end our dependence on fossil fuels the leaders of every country in this room will be woken up by calls about catastrophes of wildfires, of storms, of heatwaves, and of starvation and drought," she said.

Pakistani Prime Minister Muhammad Shehbaz Sharif said his country knows this all too well, with recent floods that have affected five million people across more than 4,000 villages, killing more than 1,000.

"As I speak to you, my country is reeling from intense monsoon rains, flash floods, mudslides and devastating urban flooding," he said. "We are facing this calamity at a time when the scars of the 2022 floods that inflicted losses exceeding $30 billion and displaced millions are still visible across our land." Anthony Albanese, Prime Minister of Australia, called this a decisive decade for climate action and said Australians know the toll of more frequent and extreme weather events like cyclones, floods, bush fires and droughts. "Australia knows we are not alone," he said.

"Warming appears to be accelerating," climate scientist Johan Rockstrom said in a science briefing that started the summit. "Here we must admit failure. Failure to protect peoples and nations from unmanageable impacts of human-induced climate change." "We're dangerously close to triggering fundamental and irreversible change," Mr. Rockstrom said.

Texas Tech climate scientist Katharine Hayhoe told leaders that every tenth of a degree of warming is connected to worsening floods, wildfires, heat waves, storms and many more deaths: "What's at stake is nothing less than everything and everyone we love." Under the 2015 Paris climate accord, 195 nations are supposed to submit new more stringent five-year plans on how to curb carbon emissions from the burning of coal, oil and natural gas. Technically the deadline was in February and about 50 nations -- responsible for one-quarter of the world's carbon emissions -- have filed theirs, including Pakistan, Micronesia, Mongolia, Liberia and Vanuatu.

All of those nations submitted on Wednesday (September 24, 2025). UN officials said countries really need to get their plans in by the end of the month so the UN can calculate how much more warming Earth is on track for if nations do what they promise. Former U.S. President Joe Biden submitted America's plan late last year before leaving office and the Trump administration has distanced itself from the plan.

"Before 2015, the world was on path for 4 degrees Celsius (7.2 degrees Fahrenheit) of warming since pre-industrial times, but now has trimmed that to 2.6 degrees Celsius (4.7 degrees Fahrenheit)," Mr. Guterres said.

However, the Paris accord set a goal of limiting warming to 1.5 degrees Celsius (2.7 degrees Fahrenheit) since the mid 19th century and the world has already warmed about 1.3 degrees Celsius (2.3 degrees Fahrenheit) since.

China, world's largest carbon polluting nation, announces new climate goal to cut emissions