Talks at the upcoming United Nations Climate Change Conference in Cancun, Mexico will not be days of "sunshine and sandy beaches", but tight schedules running back and forth from the hotel room to the meeting hall, a senior official said.

"Although expectations might be lower than they were for the Copenhagen climate talks, it will still be an important step on the long march," Su Wei, China's chief climate change negotiator, said at a press conference in Beijing on Monday for the release of the Annual Report on Actions to Address Climate Change 2010 - Challenges in Cancun and China's Actions.

The report, published in book format, covers the results of efforts to combat climate change, including specific actions taken by China, and the challenges apt to be faced at the Cancun conference, which starts on Nov 29 and runs to Dec 10.

"We are concerned whether developed countries will shoulder their responsibilities at the talks and quantify the target for cutting energy intensity," he said.

He also reiterated that China, as a developing country seeking to develop economically and eradicate poverty, will take an active and constructive role at the conference, working toward achieving a new global deal on reducing carbon emissions at next year's climate change conference in South Africa.

While climate change has largely been caused by the consumption of energy by developed nations, all countries have to deal with the consequences, he said, explaining why developing countries need to be involved in efforts to address the problem.

According to Chinese think tanks, an agreement on the climate fund is expected to be achieved at the talks in Cancun when representatives from more than 190 countries and regions meet next week.

"Developed countries have made a commitment to the climate fund. By implementing it, they will win returns from developing countries on the issue of transparency," Pan Jiahua, executive director of the Institute for Urban and Environmental Studies at the Chinese Academy of Social Sciences, said at the press conference.

Developed countries have been asking developing countries to make their emission reductions "more transparent" and open to inspection.

Chinese think tanks also indicated that one of the most difficult issues at the conference will be persuading developed countries to agree to cut their levels of energy intensity.

Using emission levels in 2005 as a gauge, China has vowed to make a 40 to 45 percent cut in emissions by 2020. In contrast, none of the developed countries have made a pledge on that scale over the past 15 years, Pan said.

Todd Stern, the United States special envoy for climate change, said earlier that Washington will stick to a target of reducing emissions 17 percent by 2020 from 2005 levels, as pledged by US President Barack Obama, despite the US Congress failing to pass a climate bill.

Zou Ji, the China country director of the World Resources Institute, a US-based think tank, said the US could still take action to reduce its carbon emissions through regulation.

By categorizing carbon dioxide as a pollutant, the US Environmental Protection Agency could regulate the emission by setting a cap, he said.

However, he warned that it would take time for the regulation to take effect and that the emission target achievable under such a system would be far lower than the 17 percent that has already been pledged.