GLASGOW, Scotland — China is at a “special development stage” that warrants its status as the world’s biggest current emitter of climate-damaging fossil fuel pollution, the nation’s senior climate negotiator said Tuesday.

Xie Zhenhua, a U.N. climate negotiator and special climate envoy for China, spoke to reporters Tuesday at the U.N. climate summit in Glasgow, Scotland. China has been much talked about as a major polluter but has been little seen at the summit. Chinese President Xi Jinping has not joined the more than 100 other world leaders at the event, addressing observers and delegates in a written message on Monday instead.

Xie, who played a pivotal role in talks leading to the 2015 Paris climate accord, underscored China’s stance that the United States and other developed nations should be the ones doing more to cut climate-damaging emissions faster, not China.

“We have already been making our biggest possible effort to address climate change,” Xie said, saying China was unable to start reining in its reliance on coal-fired power plants any quicker than it was doing.