Senior Chinese officials warned John Kerry that U.S. support for human rights threatens climate change cooperation, eliciting a pledge from President Joe Biden’s climate point-man to explain their perspective to officials in Washington.

“I will certainly pass on … the full nature of the message that I received from Chinese leaders,” former Secretary of State John Kerry, who is now Biden’s special envoy for climate change, told reporters following two days of meetings with top Chinese diplomats. “On the one hand, we’re saying to them, ‘You have to do more to help deal with the climate.’ And on the other hand, their solar panels are being sanctioned, which makes it harder for them to sell them.”