BEIJING - China plans to close about 5,000 small coal mines this year amid its efforts to improve production safety, the country's work safety regulator said on Thursday.

Many small coal mines lack sufficient means to ensure safe production and shall be closed, according to the State Administration of Work Safety.

All coal mines must finish building emergency systems by the end of June and the construction of refuge chambers should be prioritized, the administration said on Wednesday.

The requirement is a follow-up to those issued by the State Council in July 2010. These earlier requirements demanded that emergency systems be built for all coal mines within three years.

China proposes to further reshuffle its coal sector by setting higher thresholds for the scale of coal producers and encouraging mergers to form industrial conglomerates, the National Energy Administration (NEA), the country's top energy regulator, said on Monday.

The minimum standard for the scale of coal producers will be raised gradually, according to a revised NEA draft on coal industry policies.

It also says large coal enterprises will be encouraged to ally with each other or merge with smaller companies to develop bigger industrial groups.

The move came as China's coal sector is seeing softening growth and plunging prices due to overcapacity and sluggish demand amid the economic downshift.

China's coal output rose 4 percent year on year to 3.66 billion tonnes in 2012, with the growth rate 4.7 percentage points weaker than that of the previous year, data from the China National Coal Association showed.