Speaking to scientists at a Brazilian climate change and biodiversity forum in Sao Paulo, Benn also said that fears by some countries that adopting carbon curbs could stunt economic growth were misplaced.

"There is not a competition" between ecology and economy, he said, arguing for the carbon trading system to become entrenched, and for engineers to work toward favoring electric cars and wind turbines.

Reaching a deal at the December 7-18 UN climate change conference in Copenhagen is "the single most important thing we could do," Benn said.

Without it, global warming and tensions as countries try to secure resources made increasingly scarce by population growth are inevitable, he said.

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