Talks on a new global warming agreement have begun to resolve some major sticking points, the U.N. climate chief said Wednesday, sounding a promising note after months of sluggish negotiations often marked by confrontation among industrial and developing countries.

Yvo de Boer, who in the past has chided delegates for delays, gave an upbeat assessment at the end of a weeklong conference of 160 nations, the latest round in a two-year process that is due to end with the signing of an accord in December 2009.

'This has been a very important and a very encouraging meeting, said De Boer. 'The process has speeded up, and governments are becoming very serious about negotiating a result.'