BEIJING - Chinese cities need to double the number of parking lots to meet demand from rapidly growing numbers of car owners, said a report released by the China Association of Mayors on Wednesday.

For instance, the national capital city of Beijing is short of about 3 million parking lots, as it has just 2.48 million spaces for 5 million vehicles, according to the 2011 Development Report for Chinese Cities.

The report warned of worsening road traffic in Chinese cities in the future, with congestion spreading from rush hours to almost 24 hours every day.

"Roads in some major cities are overloaded with cars, putting the transport system in a fragile and unstable condition," it noted.