The two-week conference was set to finish Friday, but as so often in the annual U.N.-led talks, negotiators struggled to reach an agreement, especially on money matters.
After all-night wrangling, the latest drafts Saturday lacked the strong commitments on climate action and financing by rich countries that poor countries had hoped for. But they did include a text on "loss and damage," a relatively new concept which relates to damages from climate-related disasters.
Island nations under threat from rising sea levels have been pushing for some mechanism to help them cope with such natural catastrophes, but the United States has pushed back over concerns it might be held liable for the cleanup bill since it is the world's second-biggest emitter behind China.
A final agreement from the talks was expected Saturday.
Countries plan to adopt a new climate pact by 2015. The Doha conference focused on side issues such as extending an existing emissions treaty for rich countries and increasing financing to help poor countries deal with global warming.
Poor countries came into the talks demanding a timetable on how rich countries would scale up climate change aid for them to $100 billion annually by 2020 — a general pledge that was made three years ago.
But rich nations, including the United States, members of the European Union and Japan are still grappling with the effects of a financial crisis and were not interested in detailed talks on aid in Doha.
The latest texts included no reference to any mid-term financing targets, just a general pledge to "identify pathways for mobilizing the scaling up of climate finance."
Quamrul Chowdhury of Bangladesh, lead negotiator for the group of least developed countries, said it was the "weakest outcome" he had seen since the U.N. climate talks started two decades ago.
"We are reluctant to accept it. But anyhow we have to look at it. Most of our delegation has already left," he said.
The goal of the U.N. talks is to keep temperatures from rising more than 3.6 degrees Fahrenheit (2 Celsius), compared to preindustrial times. Temperatures have already risen about 1.4 degrees Fahrenheit (0.8 Celsius) above that level, according to the latest report by the U.N.'s top climate body.
A recent projection by the World Bank showed temperatures are on track to rise by up to 7.2 Fahrenheit (4 Celsius) by the year 2100.