U.S. climate envoy John Kerry said on Monday that the United States and China – the world’s two biggest greenhouse gas emitters – must create a partnership to tackle climate change without allowing their differences on other issues get in the way.

Kerry spoke to Reuters in front of St. Peter’s Square after he met Pope Francis, the first official to have a private audience with the pontiff since his discharge from hospital last Friday.

The former U.S. Secretary of State said he was “anxious” to meet with the current secretary, Antony Blinken, who is in Beijing now, to help determine when Kerry will go to China for talks on averting a global climate change crisis.

Kerry confirmed he has been invited to visit “in the near term” but no date has been decided.

“We’re talking about the things we very much hope China will be able to do and together with us. We have to create a partnership here. China and the United States are the two largest emitters in the world,” he said.

He said there was “no conditionality” between China-U.S. talks on climate and other issues.

China last year briefly suspended talks with the United States on climate, security and other areas in response to a visit to Taiwan by U.S. House of Representatives then-Speaker Nancy Pelosi.

Although China subsequently resumed those talks, relations between the two countries deteriorated again after what the United States described as a Chinese spy balloon traversed American airspace in February, prompting Blinken to postpone his visit until now.

“President Biden believes they (U.S.-China climate talks) should be free standing and the Chinese have said to me that they believe now that it is free standing and should be,” Kerry said.

“I think there is a general agreement that you cannot let a threat to everybody – every society, every country, every human being – that threat should not be allowed to be caught up in bilateral differences, which are real,” Kerry said.

He voiced the hope that cooperation on climate could open other possibilities for cooperation.

Kerry is having a series of meetings ahead of COP28, the latest U.N. climate summit that is to be held at the end of this year in Dubai, in the United Arab Emirates.