BEIJING: Chinese coking coal and coke futures opened down 9% on Wednesday to hit daily trading limits, as the country’s top economic planner pledged to take all necessary measures to bring the coal market back to rational.

The National Development and Reform Commission said late on Tuesday that it would bring coal prices back to a reasonable range and crack down on any irregularities that disturb market order or malicious speculation on thermal coal futures.

Thermal coal futures on the Zhengzhou Commodity Exchange, and coking coal and coke on the Dalian Commodity Exchange had plunged in night trading on Tuesday.

The most actively traded coking coal prices, for January delivery, stood at 3,442 yuan ($538.58) per tonne after touching the down limit. Coke prices fell to 4,039 yuan a tonne.

Prices of coking coal and coke have tumbled 89% and 70%, respectively, since end-June.

The drop in raw material prices also drove declines in steel prices on the Shanghai Futures Exchange. Construction-used rebar fell 1.5% to 5,382 yuan ($842.13) a tonne by 0215 GMT.

Hot rolled coils, used in cars and home appliances, dropped 1.8% to 5,590 yuan a tonne.

Stainless steel futures, for November delivery, slipped 2.5% to 20,050 yuan per tonne.

Benchmark iron ore futures on the Dalian bourse jumped 1.5% to 717 yuan a tonne.

Spot 62% iron ore prices remained unchanged at $123 a tonne on Tuesday from the previous session, according to Steel Home consultancy.