In a notice, the National Development and Reform Commission (NDRC) said it sought to "prevent volatile coal prices moves," calling for a meeting "to admonish producers for not regulating their pricing activities."

The gathering in Beijing was to be held at 2:30 p.m. (0630 GMT).

The strongly-worded notice comes a week after the NDRC asked miners to cap their price limits on 2017 contracts and pressed them to sign more long-term deals, in an apparent effort to end the months-long rally the government has said is not justified by fundamentals.

The NDRC did not respond to requests for comment.

Experts and miners say the frequency of the gatherings reflect Beijing's increasing worries about runaway prices ahead of the winter.

An official government newspaper reported on Thursday that major producer China National Coal Group Corp (ChinaCoal) has cut its thermal coal prices by 10 yuan per tonne.

Spot prices for 5,500 kcalorie thermal coal gained 4 yuan on Thursday to 697 yuan (84 pound) per tonne, data provided by Fenwei Energy showed.

(Reporting by Meng Meng and Josephine Mason in BEIJING and Ruby Lian in SHANGHAI; Editing by Tom Hogue)