President Obama and Chinese President Xi Jinping announced from Beijing today a groundbreaking joint plan for both countries to cut carbon emissions ahead of the global climate treaty expected to be finalized next year. The pact is China's first-ever pledge to stop the country's carbon emissions from growing.

Under the new accord, the United States will step up its plan to cut carbon emissions—previously 17 percent of 2005 levels by 2020—to between 26 and 28 percent by 2025. China has agreed to a 2030 deadline for its carbon emissions to peak, "with the idea being that its emissions would then start falling," the Associated Press reports.

"This is a major milestone in the U.S.-China relationship," Obama, flanked by Xi, said from Beijing. "It shows what's possible when we work together on an urgent global challenge."

The United States and China are the world's two largest emitters of greenhouse gases—climate experts have said that until the two countries reach an agreement to cut pollution, others will be reluctant follow suit. From the Associated Press:

Scientists have pointed to the budding climate treaty, intended to be finalized next year in Paris, as a final opportunity to get emissions in check before the worst effects of climate change become unavoidable. Each nation is supposed to pledge to cut emissions by a specific amount, although negotiators are still haggling over whether those contributions should be binding.

Last month, the European Union said it would cut its emissions 40 percent by 2030, compared to 1990 levels. Taken together, the U.S, China and the EU account for more than half of global emissions, and there were already indications that the world's next-biggest emitter — India — might be feeling the pressure. "The international community will now expect India to make some firm commitments," said Jairam Ramesh, the former head of India's Environment Ministry.

"This is, in my view, the most important bilateral climate announcement ever," David Sandalow, a former top environmental official at the White House and the Energy Department, told USA Today.

[Image via AP]