SHANGHAI: US climate envoy John Kerry was set to arrive in China on Wednesday for what Beijing said would be a four-day trip, as the two countries seek cooperation over the environment despite acrimony on other fronts.

In the first trip to China by a Biden administration official, the former secretary of state will visit Shanghai before travelling onto the South Korean capital Seoul.

His trip comes in preparation for President Joe Biden's virtual climate summit next week, to which the US leader has invited both Chinese President Xi Jinping and Russian President Vladimir Putin.

Beijing, which has so far not committed to Xi's presence at the summit, said Kerry would arrive on Wednesday and stay until Saturday "at the invitation of China."

Foreign ministry spokesman Zhao Lijian said that during the trip Kerry will meet with China's climate envoy Xie Zhenhua and "exchange views on Sino-US cooperation on climate change", giving no other details.

Kerry's trip comes despite a testy initial meeting last month in Alaska between top Biden officials and their Chinese counterparts.

The two sides clashed over accusations that China is violating promises of freedoms to Hong Kong and carrying out genocide against Uyghurs and other mostly Muslim minorities in the northwestern Xinjiang region.

Washington is hoping to find areas of common ground despite the high political tensions.

Kerry had told CNN that although Washington and Beijing had "big disagreements... climate has to stand alone."

The fact the trip was happening at all is a significant step, said Li Shuo of Greenpeace China.

"I don't think we should underestimate the gesture, regardless of what it delivers," he said.