UN Secretary General Ban Ki-moon is "reasonably optimistic" about a world climate conference due to open in Paris at the end of next month, he said in an interview published Thursday.
"I am still reasonably optimistic that world leaders will be able to adopt a universal protocol on climate change before the end of the year," he told Italy's Corriere della Sera daily.
"There is some slowness in the negotiating process which worries me, it's true, and there is not much time left," he said.
He added, though, "there is now a wide consensus in the world on the need to intervene on the climate."
"Almost everyone is now convinced that the cost of inaction is higher than the cost of intervening today," he said.
The UN's COP21 conference, running from November 30 to December 11, aims at securing a pact on greenhouse gases that would limit global warming to two degrees Celsius (3.6 degrees Fahrenheit) over pre-industrial times.
The last big push for a world climate deal was in Copenhagen in 2009. It nearly ended in a fiasco after rich and poor countries bickered over how to share the burden for addressing the problem.
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