UNFCCC Executive Secretary Simon Steele said we cannot lose sight of the big picture by fighting over small issues.
He urged delegates to resolve the issues as soon as possible this week, to allow time for major political decisions.
The COP29 conference began in Baku on Monday last week, with the main goal of strengthening financial resources to combat the adverse effects of climate change this year.
At the start of the conference, UN-sponsored carbon markets agreed to set standards, but climate finance talks have been slow and fractious.
Simon Steele says that valuable time is wasted on bluster, the tendency to push differences to the margins and premeditated discussions. At the same time the goodwill needed for the ambitious package is also being hurt.
He expresses his frustration that there is so much at stake, and that time is being wasted waiting for the other side to act first, and that this can only be stopped if all parties come together and bring it to a close.
Earlier, UN Secretary-General Antonio Guterres also expressed concern at the slow progress so far at the COP29 conference and warned that financial resources must be adjusted in line with the challenges facing developing countries.
…in progress