China unveiled plans Tuesday to create the world’s largest carbon market as the country continues to position itself as the world leader in the fight against climate change.

The emissions trading scheme, which the government plans to enforce in China’s power sector around 2019, will play a key role in helping the country to achieve its goal of beginning to reduce its emissions by 2030. The move sends a concrete signal to leaders across the globe that China is committed to addressing climate change at a moment when the U.S. is stepping back on the issue.

“The anticipation of this announcement, which has been building for months, is a reflection of how crucial China is,” says Nat Keohane, head of the Global Climate program at the Environmental Defense Fund. “This is the Mount Everest of climate policy.”