In a message read by a U.N. official, Ban referred to a still-burning controversy over several mistakes made in a 2007 report issued by the U.N.-affiliated Intergovernmental Panel on Climate Change which drew widespread criticisms and sparked calls for the resignation of its chairman, Rajendra Pachauri.
The report's conclusion that Himalayan glaciers would melt by 2035 turned out to be incorrect and has bolstered arguments from climate skeptics that fears of global warming were overblown.
Despite the failure to forge a binding deal on curbing heat-trapping greenhouse gas emissions at a U.N. conference in Copenhagen last December, Ban said the meeting made an important step forward by setting a target to keep global temperature from rising and establishing a program of climate aid to poorer nations.
"To maintain the momentum, I urge you to reject last-ditch attempts by climate skeptics to derail your negotiations by exaggerating shortcomings in the ... report," Ban said in the statement read at the start of an annual U.N. meeting of environmental officials from 130 countries on the Indonesian resort island of Bali.
"Tell the world that you unanimously agree that climate change is a clear and present danger," Ban said.
Indonesian President Susilo Bambang Yudhoyono said time was running out, but expressed confidence that a binding climate change deal could be forged at the next climate change summit later this year in Cancun, Mexico.
"I'm convinced that we're still not too late," he said at the Bali conference.
Indonesian Foreign Minister Marty Natalegawa said Indonesia will hold an informal meeting of all environmental ministers and officials from 130 countries Friday in Bali to discuss ways of ensuring that a binding treaty on greenhouse gas cutbacks could be forged in Cancun.
"No sealed deal happened in Copenhagen, so it's now more urgent than ever for us to work diligently between now and Mexico," Natalegawa told The Associated Press in an interview.