"We are seeing deadlocks in certain areas," says China's Xie Zhenhua.
UN negotiations aimed at preventing runaway global warming remain deadlocked less than 24 hours before the 12-day talks are set to end, China's top climate diplomat said Thursday.
Ministers working overnight along parallel negotiating tracks struggled to weave dozens of strands into a "rule book" that would bring to life the Paris Agreement on climate change.
The 2015 treaty vows to cap the rise in Earth's temperature at "well under" two degrees Celsius (3.6 degrees Fahrenheit), and 1.5C if possible.
"We are seeing deadlocks in certain areas," China's Xie Zhenhua told journalists in Katowice, Poland.
"We need to avoid straying from the principles and spirit of the Paris Agreement... We cannot accept any backsliding," Xie said through a translator.
The 195-nation Paris pact promises hundreds of billions of dollars in aid to poor nations already coping with extreme weather made worse by climate change, and -- more broadly -- to orient financial flows towards greening the global economy.
The treaty, already ratified, goes into effect in 2020.
Among the more nettlesome issues is how nations report progress in implementing voluntary national plans to reduce greenhouse gas emissions.
Wealthy nations are pushing for the rapid adoption of a unified and "transparent" set of rules that apply to all nations.
Developing countries favour a generous interpretation of the "flexibility" they are assured in the treaty.
"Only the person wearing shoes knows whether they are comfortable," Xie said, citing an "old Chinese saying".
"It should be up to each country to decide when, how frequently, and what content to provide."
"Developing countries are not comfortable at this stage of the negotiations," he added.
Nor are they likely to be reassured by the most recent attempt by Poland, which is presiding over the complex talks, to strike a middle ground.
Current climate pledges, even if fulfilled, would still see Earth's temperature rise well above 3C, a recipe for widespread human misery, scientists say.
Loss and damage
A draft of the decisions, for example, to be adopted at the consensus talks -- released late Thursday night by the host nation -- gave short shrift to another red-line issue for poor countries exposed to the ravages brought on by global warming: so-called "loss and damage".
Cutting greenhouse gas emissions and helping nations prepare for a climate-addled future have long been the twin pillars of the UN climate forum.
But more recently, a third plank of the regime was added to help nations cope with deadly heatwaves, drought and floods -- amplified by climate change -- happening today.
Pulling the pieces of the climate puzzle together, said China's Xie, was harder with Donald Trump in the White House.
"Of course I'm disappointed," he said when asked about the impending US withdrawal from the Paris pact. "How could I not be."
"The United States has been an important player in the process," he added. "We would welcome them back to the climate change arena."
Xie sidestepped a question on whether China would support a coalition of small island and least-developed states calling on all nations to raise their carbon cutting ambitions before 2020.