A national air quality monitoring network with nearly 950 monitoring stations is expected to be operational in 190 Chinese cities by the end of the year, a senior environmental official said Friday.

There are plans to build about 440 air quality observation points in 116 cities this year after 496 such points were built in 74 cities in 2012, said Wu Xiaoqing, vice minister of environmental protection, at a press conference on the sidelines of China's ongoing parliamentary session.

The network, which will publicize real-time monitoring data on air quality after being put into operation, offers an effective means of supervision for local governments to tackle the air pollution, he said.

Wu also underlined the serious pollution in south China's Pearl River Delta, east China's Yangtze River Delta, and north China's Beijing and Tianjin municipalities, the three major economic powerhouses of China.

The three areas cover about eight percent of China's total landmass but discharge five times more pollutants per square km than other areas, which worsens the air pollution in the areas, Wu said.

According to observations, those areas experience more than 100 smoggy days every year. In some cities, there are even more than 200 days with smog each year, the vice minister added.

By 2015, the ministry aims to reduce the intensity of PM2.5, air-borne particles measuring 2.5 microns or less in diameter, in those three regions by 6 percent from the 2010 level, he said.

According to Wu, the environmental protection ministry is working with other departments to establish an assessment mechanism for local governments to ensure the realization of the target.

The Ministry of Environmental Protection will also supervise and urge big-polluting enterprises to disclose their pollutant discharge information this year, he said, with the ministry expected to introduce a pollution prevention and control policy over fine particulate matter soon.

After enjoying more than three decades of rapid development and industrialization, China now has to face daunting environmental problems include the heavy smog that has shrouded large parts of the country several times this winter, forcing local residents to put on masks or even stay indoors to avoid respiratory infection.

The Chinese capital experienced only five days with clear skies in January, according to the Beijing municipal meteorological bureau.

Air pollution costs China combined economic losses equivalent to about 1.2 percent of its gross domestic product every year, if calculated in terms of treatment for pollution-related disease, according to a report released by Asian Development Bank in January.