BANGKOK: Negotiators from around the world got to work on Monday on drafting a battle plan against global warming that a top UN official warned could be the most complicated treaty in history.

Nearly all countries broadly agree that action is needed to halt climate change, which scientists warn could put millions of people at risk by century's end. But differences persist on the shape and scope of what is to be done.

"You have gathered to launch a negotiating process that is tasked with changing the course of history," UN Secretary General Ban Ki-moon said in a videotaped address to the conference's opening in Bangkok.

A total of 164 countries are taking part in the five-day meeting, which is meant to start figuring out which country will do what after 2012, when obligations run out under the Kyoto Protocol.

The talks are the first under an agreement reached at a major conference in December in Bali, Indonesia, that called for a new treaty on global warming by the end of 2009.

UN Climate Chief Yvo de Boer said negotiators faced a "daunting task" balancing competing interests from each country.

The world has "considerably less than two years to craft what may well in the end be one of the most complex international agreements that history has ever seen," de Boer told reporters.

But environmentalists accused a few developed countries of quietly trying to soften their commitment to fighting greenhouse gas emissions blame for global warming.

Fast-growing developing economies such as China and India, meanwhile, argued that they cannot be expected to make the same types of cuts as rich countries. The also want technology from rich countries to help them curb emissions.

Source : PTI