A thick pall of reddish smoke from a forest fire in Evia, some 50km from Athens, hangs over the Acropolis on Saturday. (AP)

Vienna, Aug. 26 (Reuters): The UN says momentum is building for tougher long-term action to fight global warming beyond the world body’s Kyoto Protocol, and a climate meeting starting in Vienna tomorrow will be a crucial part of the process.

Negotiators from more than 100 countries at the August 27-31 talks will seek common ground between industrial nations with Kyoto greenhouse gas caps until 2012 and outsiders led by the US and China, the biggest greenhouse gas emitters.

“Momentum is very much building,” for wider action, Yvo de Boer, the UN’s top climate change official, told Reuters of the Austrian meeting of about 1,000 senior officials, scientists and activists. “And Vienna’s going to be crucial.”

The Vienna talks will try to break a diplomatic logjam and enable environment ministers to agree at a meeting in Bali, Indonesia, in December to launch formal two-year negotiations to define stiffer long-term curbs on greenhouse gases.

“All countries need to take more urgent action,” South Africa wrote in an advance statement for the Vienna talks. “The pace of the climate negotiations is out of step with the urgency indicated by climate science.”

Chances of a deal in Bali have risen sharply after UN reports this year blamed human activities, led by use of fossil fuels, for a changing climate set to bring ever more severe monsoons, heatwaves, droughts and rising seas.

Prospects for an agreement on worldwide action to fight climate change have brightened since US President George W. Bush, a Kyoto opponent, agreed in June with his industrial allies on a need for “substantial cuts” in greenhouse gas emissions.

It is unclear exactly what “substantial” means for Washington. The European Union, Japan and Canada have all talked about a need to halve world emissions by 2050 to slow warming.

De Boer, who heads the Bonn-based UN Climate Change Secretariat, said that many nations wanted a “Bali road map” agreed in Indonesia — a two-year plan to work out a deal to succeed Kyoto which runs to the end of 2012.

A road map could include principles that a deal should include major emitters, that it should not undermine economic growth in developing nations and that rich nations should take the lead, delegates say. But many countries are unlikely to show their hands yet.