NEW YORK (NYTIMES) - Escalating tensions between China and the United States have spilled into their talks over how to stop global warming from hitting catastrophic levels after Chinese officials warned the US climate envoy, John Kerry, that political ill will could undermine cooperation.

Kerry emerged on Thursday (Sept 2) from 2 1/2 days of discussions in the northern city of Tianjin, where Chinese leaders made what he described as "pointed" comments about the worsening relationship. Kerry, a former secretary of state, said he told the officials he was focused on staving off the worst effects of climate change.

"My response to them was, 'Hey look, climate is not ideological. It's not partisan, it's not a geostrategic weapon or tool, and it's certainly not day-to-day politics. It's a global, not bilateral, challenge,'" he said on a call with reporters.

And, Kerry said, when it comes to tackling climate change, "We think China can do more".

Kerry said he and his Chinese counterpart Xie Zhenhua agreed to meet again before international negotiations in Glasgow, Scotland, in November.

Leaders from nearly 200 countries will try to agree on intensified efforts to cut greenhouse gas emissions and money to help the poorest nations prepare for the effects of global warming.

Hopes for a breakthrough in Glasgow rest heavily on whether China and the United States, the two largest emitters of planet-warming pollution, can build momentum.

Kerry said Chinese leaders briefed him on plans for cutting emissions, but added that any efforts will be insufficient as long as China continues to build the coal-fired power plants that are most responsible for planet-warming emissions.

Limiting warming to 1.5 degrees Celsius above the pre-industrial average - the point at which scientists say the effects of climate change will be catastrophic and irreversible - requires a dramatic turnaround of China's coal trajectory, Kerry said he told Chinese leaders.

"Needless to say, adding some 200-plus gigawatts of coal over the last five years, and now another 200 or so coming online in the planning stage, if it went to fruition would actually undo the ability of the rest of the world to achieve a limit of 1.5 degrees," he said, adding, "The stakes are very high."

The talks reflected the precarious role that global warming has come to play in relations between the Biden administration and Xi Jinping, China's leader. Climate change could spur the two countries to cooperate on developing emissions-cutting technology, but it is also a point of discord over whether the other side is pulling its weight.

Relations between Beijing and Washington have descended into rancour over China's treatment of Muslim minorities, its dismantling of human rights in Hong Kong, and US support for Taiwan.

On Wednesday, China's foreign minister, Wang Yi, warned Kerry that antagonism from the United States on those and other fronts could hobble climate cooperation.

"The United States should stop regarding China as a threat and adversary," Wang told Kerry, according to the Chinese foreign ministry. Work between the two nations on climate change, he said, "cannot possibly be divorced" from other geopolitical tensions.

"The US side hopes that climate cooperation can be an 'oasis' in China-US relations, but if that 'oasis' is surrounded by desert, it will also become desertified sooner or later," Wang added.

Still, Kerry and Xie have both described global warming as a threat that demands all countries work together. Signs of climate disruption this year - ferocious floods in China and Europe, supercharged hurricanes lashing the southern and northeast United States, and drought and fires afflicting the West Coast - have underscored what is at stake.

"I've made it clear consistently in all my comments wherever I am around the world that we're behind the eight ball sufficiently that we need to reach for the highest ambition," Kerry told reporters.

Administration officials said Kerry and Xie had held about 18 meetings since the start of the Biden administration, a sign that both are committed to striking a deal.

Kerry, 77, and Xie, 71, both came out of retirement after US President Joe Biden took office. Kerry on Thursday said his conversations with Xie focused entirely on climate change, and while other officials "wanted the message to be heard" on a range of issues, those concerns did not dominate the discussions.

"Kerry and Xie have been able to carve out a channel for ongoing communication on climate change, which is extremely valuable right now," Joanna I. Lewis, an associate professor at Georgetown University who studies Chinese climate policy, said by email. "Yet it is increasingly difficult to fully insulate climate change from the broader tensions."