BEIJING (Reuters) - China aims to provide clean air in its largest cities for 80 percent of each year, or more than 9-1/2 months, by 2020, up from a figure of 76.7 percent last year, the country’s cabinet said on Monday.

Workers stand on a bridge in front of the financial district of Pudong amid heavy smog in Shanghai, China December 5, 2016. REUTERS/Aly Song

Amid concern that pollution was stirring social unrest, China launched a campaign in 2014 to revitalize its tainted air, water and soil, which have been ravaged by more than three decades of breakneck industrial growth.

The clean air goal for 338 cities was laid out in a five-year development plan on ecological and environmental protection that said China would push structural reforms to cut excess capacity in polluting industries.

“With the downward pressure on the economy increasing, the contradiction between development and protection has become more prominent,” the cabinet said.Under the plan, authorities in Beijing, the capital, its neighboring city of Tianjin and the northern province of Hebei, and those along the Yangtze River economic belt will draw up eco-protection “red lines” by the end of 2017.

Other provinces and cities will have to draw up such “red lines” by the end of 2018, the cabinet said.

Total coal consumption in Beijing, Tianjin, Hebei, and the eastern Shandong and central Henan provinces will be cut about a tenth during the five-year plan period.

Consumption in the commercial capital of Shanghai, and the eastern provinces of Jiangsu, Zhejiang and Anhui will be cut by around 5 percent in the same timeframe.

Coal consumption in China’s Pearl River Delta region will also be cut by a tenth during the period, the plan stated.

China aims to cut emissions of sulfur dioxide and nitrogen oxide, both gases associated with acid rain, by 15 percent in 2020, from 2015 levels, it said.

Chemical oxygen demand, a measure of water quality, will be cut by 10 percent, while ammonia nitrogen emissions will also be reduced by 10 percent.

Last week, the province of Hebei, which borders Beijing, issued its first “red alert” of the year over severe pollution. The highest level alert for smog requires suspension of work in factories, with cars being pulled off the road.