China plans to stop building new coal-fired power plants in other nations, potentially ending one of the last sources of international funding for the dirtiest fossil fuel. 

President Xi Jinping made the announcement during the United Nations General Assembly meeting Tuesday, one year after he surprised world leaders by pledging to make China carbon-neutral by 2060. 

“China will step up support for other developing countries in developing green and low-carbon energy, and will not build new coal-fired power projects abroad,” Xi said in a prerecorded video. He’s come under pressure to back up his long-term climate goals with concrete near-term ones.

Read more: China Snuffs Out Coal Money and Boosts Its Clean-Energy Giants

The move could hobble future coal development. More than 70% of all coal plants built today rely on Chinese funding, according to the Beijing-based International Institute of Green Finance. China’s Belt and Road Initiative for overseas development projects didn’t fund any coal projects in the first half of this year, the first time that’s happened.

“This is a major step forward,” Manish Bapna, president of the Natural Resources Defense Council, said in a statement. “This opens the door to bolder climate ambition from China and other key countries, at home and abroad.”

Earlier Tuesday, U.S. President Joe Biden pledged at the UN to double the amount of money the U.S. will spend helping poorer nations fight climate change. And Turkey President Recep Tayyip Erdogan, whose nation is one of the few that hasn’t ratified the Paris climate agreement, said his parliament will work toward approving the landmark accord next month. 

Xi’s coal pledge comes as China has sought to wrest the initiative from America as the Biden administration struggles with the fallout from its rushed Afghanistan withdrawal.

Last week, China applied to join an Asia-Pacific trade pact once pushed by the the Obama administration as a way to isolate Beijing and solidify American dominance in the region. Former President Donald Trump pulled out of the deal, known officially as the Comprehensive and Progressive Agreement for Trans-Pacific Partnership, in 2017.

Xi’s speech also took aim at Biden’s Afghanistan withdrawal, though he didn’t name the country by name. “Recent developments in the global situation show once again that military intervention from the outside and so-called democratic transformation entail nothing but harm,” Xi said.

The Chinese leader also drew an implicit distinction between China’s policies and the Biden administration’s pledge to pursue “extreme competition” with Beijing. Xi repeated his position that differences between countries be handled on the basis of “equality and mutual respect” and urged countries to uphold multilateralism.

As the world’s most populous nation and top greenhouse gas emitter, China can do more than any other country to help the planet avoid the worst effects of climate change. U.S. climate envoy John Kerry and Alok Sharma, the U.K. host’s point man for COP, visited China in recent weeks seeking new green commitments. China has argued that developed nations need to do more to cut their own pollution, while raising more funds to help poorer countries decarbonize. 

Countries have been trying to produce an agreement to phase out coal power before the United Nations-backed climate talks in order to keep the Paris Agreement goal of limiting warming to 1.5ºC from pre-industrial levels within reach. China’s coal consumption is poised to hit a record this year. 

Xi’s announcement injects new hope into the Glasgow talks, which have been shaping up to be challenging. Delegates have expressed concern that tension between the U.S. and China could hurt progress on issues from raising emission reduction targets to tackling methane leaks.  

China is still in the process of developing an official road map to zero out emissions. The nation’s plan for the next five years aims to reduce carbon emissions per unit of gross domestic product by 18% through 2025 and cut energy use per unit of GDP by 13.5%. It also included plans to boost non-fossil fuels to 20% of energy use by then.