As John Podesta, President Biden’s climate envoy, wraps up three days of talks in Beijing, China’s willingness to fight global warming could depend on the outcome of this fall’s presidential election in the United States, energy experts said.

If Vice President Kamala Harris wins, the United States is likely to keep pushing nations, including China, to set ambitious targets for cutting the greenhouse gases that are dangerously heating the planet.

But if former President Donald J. Trump returns to the White House, he is expected to withdraw the United States from the global fight against climate change, as he did during his first term, and release any pressure on China to step up its efforts.

“That would at best deflate the momentum on global climate negotiations,” said Kelly Sims Gallagher, the dean of the Fletcher School of Law and Diplomacy at Tufts University.

Under the terms of the 2015 Paris Agreement, nations are considering a new set of climate goals, detailing how much their governments will cut carbon dioxide and other greenhouse gases through 2035.

But the president of China, Xi Jinping, has also made it clear that his country will not give in to pressure from the United States or any other nation when it comes to climate concerns. Last year, while John Kerry, Mr. Podesta’s predecessor as climate envoy, was in Beijing for climate discussions, Mr. Xi insisted in a speech that China would pursue its goals to phase out carbon dioxide pollution at its own pace and in its own way. China did agree, however, to displace fossil fuels with clean energy.