UN leader Ban Ki-moon said Tuesday he will press world leaders to agree a binding deal against climate warming by 2015.
There has to be a "strong, complete and binding" accord, Ban, who has stepped up warnings in recent months over the impact of accelerating temperature increases, told the UN General Assembly.
A UN conference in Doha last month extended the Kyoto Protocol, the only binding pact on curbing greenhouse gas emissions, until 2020. But the accord excludes major polluters such as China, India and the United States, which refuses to ratify Kyoto.
Ban said mobilizing action on climate change is now a "priority."
"Next year I intend to invite the leaders of the world, both individually and collectively, to mobilize the necessary political determination to adopt by 2015 a strong complete and binding instrument on climate change," he said.
His comments came after US President Barack Obama vowed to make climate change a priority when he was sworn in Monday to a second term.
"We will respond to the threat of climate change, knowing that the failure to do so would betray our children and future generations," Obama said.
Many scientists believe the Earth is set for warming that will be far above the two degrees Celsius target set by the United Nations when Kyoto was negotiated.
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