China, the world's biggest greenhouse gas emitter, wants rich nations to vow bigger cuts to emissions as part of a new international deal on fighting global warming, Beijing's top climate negotiator said on Tuesday.
The negotiator, Xie Zhenhua, said he expects "arduous" wrangling about that and other issues facing governments seeking to settle on the key parts of a comprehensive climate change pact at talks in Durban, South Africa, in late 2011.
"The negotiating talks remain arduous," Xie said.
"There's still much work that needs to be done if we're going to convert political will into progress at Durban."
Xie's paper was China's first lengthy overview of climate change negotiations since the last major round in Cancun, Mexico, late last year. Those talks brought progress on funding to cope with global warming and sharing green technology, but left key points of contention to be dealt with this year.
Although Xie revealed no new negotiating positions from China, his comments underscored the entrenched differences that will test negotiators facing warnings that droughts, floods and other extreme weather will worsen with global warming.
A main dispute is about the Kyoto Protocol.