Unlike special economic zones such as Shenzhen in South China's Guangdong Province, the experimental zones, which are generally known as the "new special zones", are being set up in Chengdu and Chongqing to pilot reforms aimed at reducing, and eventually eliminating, the income gap between rural and urban areas.

The document issued by the NDRC urged the two cities to push forward comprehensive reforms in order to achieve coordinated and balanced urban-rural development.

The reforms will target issues such as household registration, land management, social security and governance.

"The selection of the two pilot cities is necessary to explore a coordinated development model in China," explained Yang Weimin, an NDRC official.

"The ultimate aim is to ensure farmers and migrant workers enjoy the same rights, public services and living conditions as urban residents," he said.

China, which has witnessed rapid economic growth since it launched reform and opening-up policies in 1978, has also seen a widening income gap between rural and urban areas.

The per capita net income of farmers was 3,587 yuan (US$471) last year, while the per capita disposable income of urban residents was 11,759 yuan ($1,515), about 2.3 times more.

Most of China has long felt the effect of this gap. The sharp decrease in the amount of arable land and the mechanization of farming have pushed millions of farmers to find jobs in cities over the past few decades. The total number of migrant workers in big cities reached more than 900 million at the end of last year, said an editorial in China Daily.

With rural income five to six times lower than city earnings, those left behind to farm the land rely on these migrant workers for cash.

What is deeply worrying is that the urban-rural income gap has been widening in recent years because of the structural barriers depriving rural residents of equal rights.

The call is growing by both academics and citizens for a unified household registration system for rural and urban residents. The action taken by some local governments to register all households as residents only, rather than rural or urban, has pioneered the change of this unfair structure.

Pension distribution and other types of social security already delivered to rural residents in some localities are also helping close the urban-rural gap.

The two southwestern cities designated as experimental zones are of particular significance as rural residents make up more than half of each city's population.

Chongqing has a population of 31 million, 80 percent of whom live in rural areas, while Chengdu has 11 million, including 6 million rural residents.

Both Chongqing and Chengdu have the potential to help end urban-rural polarization. If successful, their experience will, hopefully, be extended nationwide, according to the NDRC.