Beijing will ban coal sales and use in its six main districts and other regions by the end of 2020 to cut air pollution, local authorities said on Monday.

According to the Beijing Municipal Environmental Protection Bureau, the districts of Dongcheng, Xicheng, Chaoyang, Haidian, Fengtai and Shijingshan will stop using coal and its related products, and close coal-fired power plants and other coal facilities.

Clean energy like electricity and natural gas will replace coal to serve residents in heating, cooking and other activities, the bureau said.

The move is a part of the capital's plan to optimize energy structure and improve air quality.

Motor vehicles, coal burning, industrial production and dust account for 31.1 percent, 22.4 percent, 18.1 percent and 14.3 percent of Beijing's PM 2.5 respectively. These airborne particles smaller than 2.5 microns in diameter are blamed for Beijing's smog.

According to official statistics, coal use accounted for 25.4 percent of the capital's energy consumption in 2012. The figure is expected to shrink to less than 10 percent by 2017.

Other high-pollution fuels, such as fuel oil, petroleum coke, combustible waste and some biomass fuel will be also banned, the bureau said.

The Beijing Economic-Technological Development Area will take the lead in giving up using high-pollution fuels by the end of this year. Other areas will gradually follow suit.