BEIJING, Jan. 5 (Xinhua) -- China is planning several major coal-group mergers and acquisitions (M&As) by 2020, the country's top economic planner said Friday.

The government will support M&As among coal firms of different scales, regions and ownerships and encourage market players to expand business from coal production to services, according to the guidelines released by the National Development and Reform Commission (NDRC) and 11 other government agencies.

Coal firms are also encouraged to conduct M&As with players in related sectors, including power, coal, chemicals and steel, to fully integrate their resources in the wider industrial chain.

The efforts aim to push the reduction of excess coal capacity, upgrade technology, improve resources allocation and production safety.

Chinese leading power generator China Guodian Corporation and coal miner Shenhua Group last November merged into energy conglomerate China Energy Corporation, making it the world's largest company in coal mining, thermal power, renewable energy and coal-to-liquid conversion.

By the end of last year, the number of coal mines in China dropped to about 7,000, from 10,800 in 2015, according to the NDRC.