Bangkok, Apr 5: More than 160 nations, including India, agreed tonight on the first step to drafting an ambitious new treaty on global warming after hours of haggling between rich and poor countries.

The five-day conference in Bangkok also looked for the first time to consider regulating emissions from airplanes and ships, a rapidly growing source of the pollution blamed for heating up the planet.

But rich and poor countries are sharply divided on how to tackle global warming, despite growing fears that rising temperatures could put millions of people at risk by the end of the century.

The talks set a work plan of four meetings next year to complete a pact by the end of 2009 which would follow the landmark Kyoto Protocol, which requires rich nations to slash gas emissions blamed for warming. The United States shunned the Kyoto Protocol, saying it is unfair by imposing no requirements on fast-growing emitters such as China and India. The Bangkok conference ended past midnight on the final day, hours after the scheduled close, with bickering over a Japanese proposal to hold talks soon on the so-called "sectoral approach," in which each industry is judged separately on eco-friendliness.

"There were differences of opinion on different topics," UN climate chief Yvo de Boer said. "It takes time to find a way out and they did." Poor nations fear the sectoral approach makes greenhouse gas cuts easier for rich countries because they have cleaner technology, and that it could be a backdoor way to legally require them for the first time to cut emissions.

"I think it needs to be explained better," de Boer said of the Japanese proposal.