THE United States resisted pledging steeper cuts in greenhouse gas emissions by 2020 despite calls by poor nations yesterday at the start of a United Nations conference for tougher action to avert storms, droughts and rising seas.

About 200 nations met in Doha, Qatar for annual UN talks on global warming with little prospect of a breakthrough and recriminations over how to keep alive hopes of a new, global UN deal to fight climate change meant to start in 2020.

"We're sleepwalking off a cliff," Alden Meyer of the Union of Concerned Scientists said.

There was a lack of ambition to confront rising world greenhouse gas emissions at the two-week meeting, the first in an OPEC nation, he said.

US deputy climate envoy Jonathan Pershing said President Barack Obama was sticking to his 2009 goal of cutting emissions by 17 percent below 2005 levels by 2020.

"I do not anticipate that the United States will modify the commitment we have made," he told a news conference.

Washington was taking aggressive action to cut emissions and its national emissions may have peaked, he said.

China's chief delegate Su Wei insisted that the rich should extend the UN's Kyoto Protocol, the existing plan that binds developed nations to cut emissions by at least 5.2 percent below 1990 levels between 2008 and 2012.

"If there is not agreement on a second commitment period of the Kyoto Protocol, I think that would be disastrous for talks on future enhanced action after 2020," he said, referring to a global pact meant to be agreed by 2015.

"If we cannot agree on immediate actions, how can anyone agree on future actions?" he said, urging the rich to do more.

A group of more than 100 developing nations also said developed countries should do more to avoid damage on a "previously unimaginable scale."

Extreme weather

The European Union has also said that it has no plans to increase its goal for cutting emissions to 20 percent below 1990 levels by 2020. The US goal corresponds to a cut of 3-4 percent below 1990 levels by 2020.

Pershing said extreme weather, including superstorm Sandy and widespread drought in the US, "are certainly changing the minds of Americans" who have often been skeptical about the need for more action on climate change.

A UN study last week said the world was on target for a rise in temperatures of between 3 and 5 degrees Celsius because of increasing emissions. A UN conference two years ago agreed to limit any rise in temperatures to below 2 degrees above pre-industrial times. But greenhouse gas levels hit a record in 2011, despite the world economic slowdown.

Christiana Figueres, head of the UN Climate Change Secretariat, said countries needed to act now to keep down costs of confronting climate change.

Most countries favour extending the 1997 Kyoto pact. Developing countries and Kyoto backers say it is vital developed nations lead the way toward the new worldwide accord meant to start in 2020. Failure to extend Kyoto would leave only national actions, with no legally binding UN framework.