In addition to the growing attention to the six core cities, the ministry also emphasized existing joint efforts to control smog in the northern trilateral region, Chen said.

By the end of January, it had established a regional network to share monitoring information about major companies in polluting industries.

Additionally, the governments of Beijing, Tianjin and Hebei province have conducted joint inspections and held regular regional meetings. Among the next targets, the small yet heavily polluting plants scattered around the region will be a major one, the ministry said.

Last year, only 21.6 percent of the 338 monitored cities reached their targets for air quality standards. But China has seen a gradual improvement in air quality, especially in the reduction of concentration of PM2.5 — airborne pollutants with a diameter of less than 2.5 microns that can penetrate the lungs and harm health — which fell by 14.1 percent year-on-year, the ministry said.

With the economy weakening, many local governments are reluctant to take steps to reduce air pollution, since restrictions could shut down companies and affect economic growth and society, Chen said.

But it's time to change the growth concept to put more focus on sustained growth with a better environment, the minister added.

zhengjinran@chinadaily.com.cn