The US and China, the world’s biggest polluters, vowed to step up joint action to tackle climate change in a revival of collaboration that’s likely to offer crucial momentum for UN talks in Dubai opening later this month.

Both nations will back global efforts to triple renewable energy capacity by 2030, accelerate the domestic buildout of green power to replace coal, oil and gas, and advance cooperation to limit emissions of nitrous oxide and methane, two particularly pernicious greenhouse gases, the US State Department and China’s Ministry of Ecology and Environment said in identical statements.

Future emissions-cutting pledges under the Paris Agreement will target all greenhouse gases, according to the declaration — a shift from China’s focus on carbon dioxide.

The renewed cooperation represents the culmination of months of talks between the two superpowers — and come hours before US President Joe Biden meets with Chinese President Xi Jinping on the sidelines of the Asia-Pacific Economic Cooperation summit in San Francisco.

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The steps signal a further easing of tensions between the US and China — and a return to more productive bilateral climate diplomacy before the COP28 summit. Earlier joint declarations on climate by Beijing and Washington have paved the way for global pacts.

“Engagement between the two largest emitters” amounts to “a precondition for meaningful global progress,” said Li Shuo, incoming director of the China Climate Hub with the Asia Society Policy Institute. “The US-China talks will help stabilize the politics when countries meet in the UAE.”

The US and China will work in Dubai to encourage “substantially more ambition” to arrest planetary warming, including support for a Paris Agreement aim of limiting global average temperature growth to “well below 2 degrees C,” according to the statements.

Climate experts praised the countries’ commitment to extend the scope of future emission-cutting pledges beyond carbon dioxide. The sides have also set benchmarks for a “global stocktake” of emissions-cutting progress at COP28, which raises the prospect the exercise will encourage nations to ratchet up their ambition, said Alden Meyer, senior associate with research group E3G.

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China and the US expect meaningful cuts to be made to power sector emissions before 2030, the nations said in their statements. President Xi Jinping previously pledged China would peak its overall emissions before the end of the decade.

The statements imply “a reduction in emissions from China’s coal plants very soon,” said Joanna Lewis, an expert in international policy at Georgetown University.

China relied on coal for more than 60% of electricity generation last year, according to the International Energy Agency.

Beijing and Washington left some major issues unresolved, as developing and developed nations spar over the scale and source of climate finance. The declarations also leave open the issue of whether countries will commit to a phaseout of fossil fuels at the UN summit, said David Waskow, director of the World Resources Institute’s International Climate Initiative.

The US and China had previously jointly pledged to enhance climate action as part of a working group in 2021. That activity was put on ice for most of last year, following the controversial visit of then-House Speaker Nancy Pelosi to Taiwan.

Major face-to-face talks resumed in Beijing in July between US Special Presidential Envoy for Climate Change John Kerry and his Chinese counterpart, Xie Zhenhua, and continued Nov. 4-7 in Sunnylands, California.

(Updates with expert comments and further details from sixth paragraph)

Author: Jennifer A. Dlouhy and Dan Murtaugh