Xi has made ecology and the environment a centerpiece of his fact-finding trips to the nation's 31 provincial areas, highlighting the importance of this issue to China's long-term development.

During an inspection trip of Beijing in February 2014, when air pollution was the top public concern, he made a strong appeal for treatment of pollutants, especially PM2.5 particulate matter.

Xi told city officials during the trip that the primary task of improving air quality was to curb PM2.5. He also laid out measures to reduce the use of coal, cap the use of vehicles, and to adjust the industrial structure.

In September 2013, the State Council, China's Cabinet, introduced an action plan to prevent and control air pollution, including a series of steps to cut emissions of major pollutants, renovate power plants, and encourage the use of non-fossil fuels.

Preventing and controlling pollution was listed as one of the three critical battles for the nation in Xi's report to the 19th National Congress of the CPC in 2017.