Air pollution control remains at the top of the government's agenda, and both the National Development and Reform Commission - the country's economic planner - and the Ministry of Ecology and Environment, have vowed to improve air quality.

"We will make a major push to promote conservation and efficient use of energy, and urge key localities to cut coal consumption by replacing it with alternative energy and by using coal in a cleaner and more efficient way," according to the draft report submitted to national legislature by the commission.

Coal is one of the major contributors to air pollution in China. The commission also promised to effectively promote clean energy sources for winter heating across northern China, and coordinate resources needed to ensure cleaner use of coal in nonindustrial sectors.

The average density of PM2.5 in the country decreased by 10.4 percent year-on-year in 2018. Despite the achievement, the country saw an increase in the pollutant's concentration in some areas in the past two months, and some key regions even experienced deterioration, said Liu Bingjiang, a national political adviser and head of air quality management at the Ministry of Ecology and Environment.

He said the local industrial structure in the Beijing-Tianjin-Hebei cluster, which has a large number of air polluting enterprises and industries, needs to be upgraded to improve the region's air quality. The high reliance on diesel trucks for transportation also needs to be changed, he added.

The efforts of some local governments in the region have relaxed, Liu said, warning that all officials who fail to achieve air pollution targets in their regions will not escape punishment.

Referring to the fight against air pollution as a war, Liu said: "War requires a serious commitment. We should keep our promises with action, and there must be progress. Those who fail will be fully held accountable."