BEIJING, China (AP) -- An effort to clean Beijing's air ahead of the Olympics by removing cars from its clogged roads began Monday, but there was no immediate difference in the capital.
Skies remained smoggy and traffic was bumper-to-bumper during afternoon rush hour on freeways and Chang An Avenue, which cuts through the heart of the city.
Under the edict, half of all government and Communist Party cars were not being used from Monday until July 19, the city said in a notice on its Web site.
On July 20 another regulation kicks in that will allow vehicles on the road only on odd or even days, depending on their license plate numbers.
New sports venues and $40 billion spent to improve China's infrastructure have not disguised the fact that Beijing's air quality remains a contentious issue for the games.
International Olympic Committee president Jacques Rogge said earlier that outdoor endurance events lasting more than an hour would be postponed if air quality was poor.
Organizers announced details last week of a plan to pull half of Beijing's 3.3 million vehicles off the roads during the Olympics to help clean the city's air for the games.
The auto ban is part of an anti-pollution plan that also will halt construction and heavy industry during the Olympics, which begin in seven weeks.
In addition, 300,000 heavy polluting vehicles -- aging industrial trucks, many of which operate only at night -- will be banned starting July 1.