Countries will have to make far greater cuts in greenhouse gas emissions if the world is to limit the rise in global temperatures to two degrees Celsius or less, the UN has warned.
Commitments made since December's Copenhagen climate conference have been insufficient, the United Nations Environment Programme (UNEP) said in a report at its annual meeting on the Indonesian island of Bali.
"No one should assume that the pledges will be enough," UNEP director Adrian Steiner said.
"Countries will have to be far more ambitious in cutting greenhouse gas emissions if the world is to curb a rise in global temperature."
The Copenhagen summit struck a last-minute compromise that set a goal of limiting warming to two degrees Celsius (3.6 degrees Fahrenheit) and pledged a total of nearly 30 billion dollars in aid to poor countries by 2012.
But it did not spell out the means for achieving the warming limits, and the emissions pledges were only voluntary.
Indonesian President Susilo Bambang Yudhoyono warned the ministers and officials gathered on Bali that the clock was ticking on efforts to forge a global treaty on climate change to succeed the Kyoto Protocol.
"We have to conclude the climate change negotiations in Mexico at the end of the year," Yudhoyono noted at the opening session on Wednesday. "I think it is not too late."
Other environment ministers and climate officials echoed his call although the United States, which is the world's second biggest polluter after China, did not send any ministers to Bali.
International climate negotiators are due to meet on April 9 in Bonn to draw up a programme for the rest of the year looking towards the ministerial-level meeting opening on November 29 in Cancun, Mexico.
Green groups and most scientists say the document adopted in Copenhagen, a limited pact made after China angrily ruled out binding commitments, falls far short of what is necessary to curtail global warming.
The European Union is pledging to cut its greenhouse gas emissions by 30 percent by 2020, compared to 1990 levels, if other major powers do the same. But cuts outlined by the United States and China fall well short of that.
