Earlier reports have said the higher cost of Euro IV fuel will not be passed on to consumers at a time when inflation is at a decade high.

Beijing's smoggy skies, clouded by a mix of auto exhaust, factory pollution and construction dust, are one of the most pressing concerns of the city, international Olympic officials and athletes ahead of the Games, which open on Aug. 8.

The city is building miles of subway lines and has reduced public transport fares to discourage driving in the traffic-clogged capital, yet some 1,000 new cars hit the road every day in Beijing.

But the city is sparing no effort to ensure clear skies.

Weather forecasters are expected to know a week in advance if there is a threat of rain on the opening day and will take measures that include firing missiles into the sky to disperse the clouds, the China Daily reported.

Scientists cleared clouds before they reached Shanghai on Oct. 2 last year, the opening day of the Special Olympics there, the report said, quoting Zheng Guoguang, the head of the China Meteorological Association

"It is unrealistic to speculate now on weather conditions of the Beijing Games and what moves we'll take then," Zheng said. "We have the confidence and are ready."