"The United States is going to be a partner -- we need to be a partner to developed countries and to developing countries," said Todd Stern, U.S. President Barack Obama's special climate envoy.

The United States will be "powerfully and fervently engaged" in this round of UN climate talks, said Stern.

The Bonn Climate Change Talks, as the first major UN climate negotiating sessions this year, kicked off in Bonn, Germany on Sunday. It will run through April 8, with more than 2,000 participants from 175 countries including government delegates and representatives from business and industry, environmental organizations and research institutions.

The U.S. position was keenly observed in the talks, as it would be the international debut of Obama's climate change policies since he was sworn into office on Jan. 20. Obama has shown a quite different attitude toward climate issues from that of his predecessor, George W. Bush.

Stern stressed that "we all have to do this together. We don't have a magic wand."

He also defended the U.S. government's goal of reducing U.S. carbon emissions by roughly 16 percent in the next dozen years. It was far short of the target under discussion by the industrial world, which is eyeing cutting emissions by 25-40 percent below 1990 levels by 2020.

Yvo de Boer, executive secretary of the UN Framework Convention on Climate Change (UNFCCC), welcomed Obama's new policies, saying it would be "useful" for finding a political solution for climate change talks.

He also pointed out that developing countries would only agree to a new climate package if industrialized nations set clear targets for the reduction of emission.

An article published by Oxfam, an international relief and development agency, just before the talks asked rich countries to take bigger and bolder actions in climate negotiations in Bonn, as rich countries created the climate chaos, but it is the world's poorest people who are already suffering most from its effects.