But even the most ambitious plans to reduce greenhouse gases, explored in depth in a recent IEA report, might not be enough to stop such warming, said Mandil.

The IEA set out six scenarios for dealing with global warming in the report on energy technology options, part of its role as energy advisor to the 26 leading industrial nations of the world.

But scientists told Reuters even the most ambitious of those would not be enough to prevent a two degree rise in global temperatures.

"I agree with those scientists," Mandil told reporters. "Probably even in these scenarios we won't prevent a (two degree) increase in average world temperatures. Probably.... it is too late by now."

"Reducing carbon dioxide emissions is part of the solution. Another part is adaptation (to higher temperatures), but we haven't addressed that."

Mandil said that all technologies available would need to be applied if the energy industry were to create a sustainable future. Those included carbon dioxide capture and storage, increased energy efficiency and more use of biofuels.