Du stressed the improving air quality required long-lasting and consistent efforts. "We have fought for the goal (of better air quality) for almost 10 years, and will continue our efforts in this path."

He didn't disclose a detailed environmental agenda for the Games period but said that measures would include partial motor vehicle bans, limiting polluting procedures at construction sites and ordering heavily-polluting factories to cut emissions or discharges.

He assured the audience that Beijing would fulfill the environmental commitment it made when bidding for the Games.

"Better air circulation and ample rainfall, which are usually seen in the summer, will help dissipate pollutants," he added.

"Under normal meteorological conditions, air quality during the Olympics will meet the national and World Health Organization (WHO) standards," Du said, stressing that "there is not much room for doubt".

Hu Fei, a researcher with the Institute of Atmospheric Physics under the Chinese Academy of Sciences, however, warned that the government should prepare for a long and tough fight against air pollution, citing inhalable particles and ozone remain major obstacles to the "Green Olympics" goal.

It might not be a big problem to improve Beijing's air quality during the Games as the weather in August was usually cooperative and the government could take measures to temporarily close down the polluters and impose traffic controls, said Hu.

"However, this is an expedient and by no means a permanent measure. What if some extreme weather event happened during the Games? It may turn the years of effort into nothing," he said. "Beijing should work hard to reduce the density of inhalable particles and ozone to guarantee a long-term effect."

(Xinhua News Agency February 28, 2008)