China will use a three-day meeting on climate change as a platform for public diplomacy to show the world its sincerity in reducing carbon emissions.

The event will also serve to strengthen climate change talks and help the Cancun conference - scheduled for the end of the year - achieve a legally-binding document, a top policy advisor has said.

From Friday, about 20 climate change and environmental ministers from such countries as Denmark, Germany and Mexico will join 600 officials, experts and entrepreneurs worldwide at a high-level climate change forum in Beijing.

"As the host, we aim to create a platform for key players worldwide to exchange thoughts and positions," said Zheng Xinli, executive president of the China Center for International Economic Exchanges (CCIEE), an influential think tank headed by former vice-premier Zeng Peiyan.

"We hope these efforts will help the Cancun conference achieve a substantial result."

Beijing considers the latest event an opportunity to build trust with both industrialized and developing countries on the bumpy road to Cancun. Some Western media and politicians labeled Beijing a "hijacker" of the Copenhagen climate change summit last December, which China said was unreasonable.

"Apart from governmental negotiations, we need to utilize various pragmatic and flexible approaches to unite developing countries and help industrial nations understand our collective appeal," Zheng told China Daily.

Based on the lessons from previous negotiations, the event is a signal that China will try hard to make its voice heard not only at the negotiating table with other governments, but also at other occasions of public diplomacy, Zheng said.

The event is being held prior to the UN's mid-year climate change negotiations in Bonn next month.

Premier Wen Jiabao, who this week pledged that the government would use "iron-handed" measures to realize its green targets, is scheduled to meet the foreign environment and climate ministers and opinion leaders on Friday afternoon.

Vice-Premier Li Keqiang will make clear China's consistent position on climate change on Saturday morning at the opening ceremony of the forum.

Zheng said for China and other developing countries, the biggest danger ahead is that some developed countries plan to abandon the Kyoto Protocol, which requires industrial nations to accept internationally-binding carbon reduction responsibility.

"We, along with other developing countries, urgently demand that industrialized countries continue to implement the Kyoto Protocol after 2012 and take on binding responsibility for carbon cuts," said Zheng, a policy advisor to China's highest leadership for years.

"The Kyoto Protocol is the basis for fruitful Cancun negotiations."

China is expected to use "harsher measures" in the coming 5-10 years in an effort to realize the goal of cutting carbon intensity by 40-45 percent by 2020 from 2005 levels, said Zheng.

The goal, announced by Wen prior to the Copenhagen summit, was set after the country moved closer to realize the target of reducing energy intensity per unit of gross domestic product by 20 percent from 2006 to 2010.

"The new target is ambitious and faces mounting challenges ahead," said Zheng. "But China will keep its promises."