The world will have to face serious consequences for not taking proper action to deal with climate change, the head of the UN Intergovernmental Panel on Climate Change (IPCC) said Monday.

It is very important that the world clinch a "strong enough agreement" at the upcoming UN climate change conference in Copenhagen in December, "something that commits all the nations of the world to taking action on the basis of the common but differentiated responsibilities," Rajendra Pachauri told a press briefing at UN Headquarters.

"If we don't get a good agreement in Copenhagen, then clearly the implications, the humanitarian as well as economic costs of that, will be very large, and unfortunately they will be particularly serious for the most under-privileged communities in the world," he said. "We have to be really concerned about that."

Such a failure would also leave open the possibility of putting global peace and security at risk, he said.

The fact that the IPCC and former U.S. Vice President Al Gore were awarded the 2007 Nobel Peace Prize is the clear recognition of the link between climate change and peace and security, he said.

"That will certainly be threatened if you don't take action. There is no question about that," he stressed.

Pachauri welcomed the recent agreement reached by the Group of Eight (G8) leaders to limit global warming to within 2 degrees Celsius above pre-industrial levels.

"The world will have to ensure that global emissions peak in 2015 and then decline rapidly after," he said.

(Xinhua News Agency July 21, 2009)