China's coal-rich province of Shanxi will halt approval for new coal mines until 2020 in the face of plummeting coal prices and shrinking demands, the provincial government said Wednesday.

Sources with the Shanxi Coal Industry Association said coal output growth slowed to 1.47 percent last year from 12 percent in 2011. The provincial bureau of statistics expects a slight fall in output in 2015.

In 2013, output in the country's second most productive coal producing region was 960 million tonnes, only 71 percent of its capacity.

Combined net earnings of local coal producers in the Jan.-Sept. period were only 5.9 percent of the profits a year previous. Net profit for each tonne of coal was only 2.59 yuan (40 U.S. cents).

Coal mine development has caused serious ecological issues in Shanxi, leaving little room for output growth.