China will speed up the development of three key economic zones in its west which are expected to form the framework of the region's economy, according to sources with a symposium held Thursday in Beijing.

The three economic zones refer to the belt along the railway linking Urumqi, Lanzhou and Xi'an, the belt along the upper reaches of the Yangtze River, and the area along the Nanning- Kunming railway and the expressways leading to the coastal areas in southwest China.

During the nationwide drive to develop China's vast western areas, priority should be given to certain economic zones with dense population and convenient transportation, officials with the Chinese State Council said.

Covering a numerous large industrial cities and mines, the three economic zones are expected to promote development of the west China regio as well as their neighboring areas, officials said.