MANILA: Dalian coking coal and coke futures moved in and out of positive territory on Tuesday, mirroring market unease over regulatory intervention in China to tame surging prices of coal in particular. The most-traded January coking coal on China's Dalian Commodity Exchange rose as much as 3.9% before falling by up to 3.4% within the first two hours of trading. It was up 0.2% at 2,956 yuan ($463) a tonne by 0300 GMT.

Coke - the processed form of coking coal and the primary reducing agent for key steelmaking ingredient iron ore, rose 3.3% to 3,800 yuan a tonne, after slumping 2.4% in early trade. "The collective price of coal-related futures has turned from strong to weak," analysts at Sinosteel Futures wrote in a note, attributing the market volatility to Beijing's resolve to ensure supply and stabilize prices.

"They will implement intervention measures on coal prices in accordance with the law, causing market panic," they said. On Tuesday, China's top economic planner - the National Development & Reform Commission (NDRC) - said it was studying a mechanism to stabilise coal prices. Tight supply in China, the world's biggest steel producer, propelled coking coal and coke prices to record peaks earlier this month. Dalian iron ore opened weaker but later rose as much as 2%, while the benchmark contract on Singapore Exchange was up 2.2%.