China's legislators on Wednesday expressed their worries over the environment in the country's western area, warning that it cannot follow the way of development in eastern part that caused serious environmental pollution.

In the ongoing bimonthly session of the Standing Committee of the National People's Congress (NPC), the top legislature, deputies held group deliberations on a government report of the implementation of the western development program, known as the "Go West" strategy.

Since 2001 when the strategy began, over 8.5 trillion yuan (1.4 trillion U.S. dollars) has been sent to western region, building major infrastructures and improving the people's livelihood.

However, legislators are worried that development in the vast western area will lead to heavy pollution and ecological degradation, at the time that poor air quality is often reported in eastern and northern China.

The session coincided with that northeastern China was shrouded with heavy smog, closing highways and schools. An index measuring PM2.5, or particulate matter with a diameter of 2.5 micrometers (PM2.5), reached a reading of 1,000 in some parts of Harbin, the capital of northeastern Heilongjiang province.

"Development in western region should not repeat the way of that the east has experienced -- pollution first, and treatment later," said Zhang Ping, vice chairman of the NPC Standing Committee and former head of the National Development and Reform Commission.

Zhang added at the group deliberation that together with lack of water, roads and education resources, vulnerable ecosystem in the West is a bottleneck hindering development of the region.

As China's developed eastern region is upgrading its industry structure and transferring some low-end industries to neighboring countries and the west region, legislators are worried the trend will affect the west's vulnerable ecosystem.

Deng Changyou, another member of NPC Standing Committee, said development in western region should not surpass the level that the environment can bear, and industries with heavy pollution and high energy-consumption should be limited to be transferred to the West.

Mu Dongsheng, a deputy to NPC and vice chairman of the Provincial People's Congress of Qinghai Province in northwest China, said a long-term compensation mechanism for environmental protection should be established in a bid to subsidize the area that is limited to some development projects for the purpose of environmental protection.

"Only with this way, environmental protection in the West can be sustainable, added Mu.

In another development, Zhang Dejiang, chairman of the NPC Standing Committee, presided over the NPC Standing Committee chairpersons' meeting Wednesday afternoon, on which senior legislators heard a report about suggestions for revision of the consumer rights law.

The bi-monthly session runs from Monday to Friday. Endi