Climate change negotiation is an urgent issue cannot wait too much bargaining and all sides should make their utmost efforts to ensure progress of the Cancun meeting, China's top climate change negotiator Su Wei told China Daily Tuesday after the Opening Ceremony of the United Nation's Climate Change Meeting in Cancun.

"Moderate flexibility is needed by all parties in order to push forward the climate change negotiations, but one thing cannot be compromised is the issue of mankind's living and development, as the climate change has posed great pressure on that," Su said.

"I don't suggest parties bargain a lot on the climate change issue, instead, I think countries should clarify their individual responsibilities and exert one's utmost capability in dealing with the challenges," Su said.

Core issues of the Cancun meeting include technology transfer, application, mitigation and finance, Su said, and China expects balanced progress can be achieved to lay a sound foundation for a future legally binding treaty, Su said. As always, China is trying its utmost to play a "constructive and positive" role in the Cancun meeting, he said.