(Corrects year in first paragraph to 1850 from 1950)

LONDON, Dec 13 (Reuters) - The 11 warmest years on record have all occurred in the last 13 years, with 2007 set to be the seventh hottest since 1850, according to provisional global data from the UK's Met Office and the University of East Anglia.

The top eight hottest years since global records began 157 years ago are all this century, except the hottest of all, 1998, when the mean global temperature was 0.52 degrees Celsius above the long-term average for 1961-1990.

The announcement comes as the European Union clashed with the United States over Washington's resistence to settting global targets for fighting climate change at U.N. talks in Bali.

Scientists and politicians are in Indonesia to discuss how to reduce greenhouse gas emissions blamed for increasing global temperatures.

"The last few days have provided an important platform for debate and confirms the need for swift action to combat further rises in global temperatures because of human behaviour," Vicky Pope from the Met Office's Hadley Centre, who has been attending the conference, said in a statement on Thursday.

The last time annual mean global temperatures were below the long-term average was in 1985, the Hadley Centre, the UK's leading climate research body, said on Thursday. Mean surface air temperatures have continued on an upward trend ever since.

According to global temperature data for January to November, 2007 is on track to be 0.41 degrees Celsius above the long-term average and would probably have been even hotter had it not been for the cooling effect of the La Nina weather phenomenon.

"The year began with a weak El Nino -- the warmer relation of La Nina -- and global temperatures well above the long-term average," Phil Jones, director of UEA's Climatic Research Unit, said. "However, since the end of April the La Nina event has taken some of the heat out of what could have been an even warmer year." (Reporting by Daniel Fineren, editing by Anthony Barker)

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