Chinese officials can’t blame the United States for their failures to prosecute an aggressive policy to reduce emissions, according to one of President Joe Biden’s top aides.

“It’s on them,” White House national security adviser Jake Sullivan told reporters Monday, as the U.S. delegation prepared for the launch of an international climate conference in Glasgow. “They are a big country with a lot of resources and a lot of capabilities, and they are perfectly well capable of living up to their responsibilities. It’s up to them to do so.”