TAIYUAN, Jan. 8 (Xinhua) -- A total of 11 prefecture-level cities in China's coal hub Shanxi Province have established no-coal zones in its urban districts to tackle air pollution, local authorities said.

The storage, sales and use of coal are all banned in the no-coal zones, according to the Shanxi Provincial Department of Ecology and Environment.

The exceptions are made for coal-fired electricity generators, large-scale heat providers and industries that use coal as a raw material.

The authorities said the area covered by the no-coal zones will be gradually expanded. Meanwhile, the sale or burning of low-grade coal among residents has been banned in the whole province.

For those who violate the rules, market regulators above the county level will order them to make rectifications and will confiscate raw materials, coal products and illegal gains. A fine up to three times the value of the goods will be imposed.

Shanxi is under big pressure to curb air pollution. In the first three quarters of last year, 7 out of 20 cities with the worst air quality were in Shanxi.

With a quarter of China's proven coal reserves, Shanxi shut down 36 coal mines in 2018, cutting 23.3 million tonnes of production capacity.

According to a plan regarding the reduction and reconstruction of the coal mining industry in the province, coal mines with an annual output below 600,000 tonnes will be closed by 2020.