"This is no time for finger pointing. The blame game is a recipe for mutually assured destruction," Guterres said, after flying back to Egypt from Bali where he had attended a G20 leaders meeting.
"The time for talking on loss and damage finance is over -- we need action."
With the two-week COP27 conference in Egypt officially due to wrap up on Friday, negotiators faced a long night as they scrambled to find a compromise over the contentious issue of "loss and damage" and prevent the talks from collapsing.
Guterres said there was "clearly a breakdown in trust" between developed and emerging economies, adding that the most effective way to build confidence would be to find an "ambitious and credible agreement" on loss and damage and financial support for vulnerable countries.
Hours after Guterres's intervention, Sameh Shoukry, the COP27 president, urged delegates to approach the last hours of talks with "urgency".
"We are not where we need to be in order to close this conference with tangible and robust outcomes," he said at a session late Thursday.
Developing nations least responsible for global emissions are pushing rich polluters to agree at COP27 on the creation of a fund to compensate countries facing huge losses from climate impacts.
After dragging their feet over loss and damage over concerns it would leave rich nations legally exposed to open-ended demands for compensation, the United States and European Union somewhat softened their position by agreeing to discuss the issue at COP27.
European Commission Vice President Frans Timmermans proposed the establishment of a "loss and damage response fund for the most vulnerable countries" as a compromise.
But he also said that the funding should come from a "broad donor base" -- code for China, the world's top polluter and second biggest economy, to participate.
The deadlock on loss and damage is holding up agreement on a broad range of issues that nations are hoping to address at COP27.
Developed countries want countries to reaffirm their commitment to meeting the aspirational goal of limiting global warming to 1.5 degrees Celsius -- a tough target as CO2 emissions are expected to hit an all-time high this year.
Timmermans said that for the EU, the 1.5C target and loss and damage "are two sides of the same coin".
"The climate clock is ticking, and trust keeps eroding," Guterres said.
"The parties at COP27 have a chance to make a difference –- here and now. I urge them to act -- and act quickly."
