BEIJING -?The Ministry of Environmental Protection (MEP) on Thursday urged local governments of five cities with declining air quality to fully implement the national plan for clean air.

The MEP on Thursday interviewed the top local-government officials of five cities -- Changzhi in Shanxi Province, Anqing in Anhui Province, Jining in Shandong Province, Shangqiu in Henan Province and Xianyang in Shaanxi Province -- as their air quality had worsened in the first quarter of the year.

The MEP found that major air pollutants in the five cities, such as PM2.5, PM10, carbon dioxide and nitrogen dioxide, had all increased. Enterprises in those areas violated laws on environmental protection by illegally emitting pollutants.

It was found that the cities also had severe levels of dust, and the burning of grass and garbage was not controlled. The MEP said that all the pollution could be traced to the fact that the cities had failed to roll out environmental protection measures.

The MEP urged the local governments to raise the awareness of environmental protection, improve their working mechanisms, strengthen pollution treatment and better supervise.

The five cities were asked to submit their plans for rectification to the MEP in 20 working days.

The officials sincerely accepted the MEP's criticism, and all promised to draw up their rectification plans as soon as possible.