Nippon Steel, the world’s No.4 steelmaker, will keep on hunting for stakes in coking coal and iron ore mines to ensure a stable supply of essential raw materials and mitigate the potential impact of price volatility, its executive said.

A Glencore-led consortium, including Nippon Steel, sealed one of the mining sector’s biggest deals in years this month, agreeing to buy Canadian miner Teck Resources’ steelmaking coal unit for $9 billion. The Japanese company will pay around $1.34 billion for a 20% stake.

“Coking coal prices are expected to rise as supply will get tighter in the medium term as there has been little investment in mines due to carbon-neutral push,” executive vice president Takahiro Mori told Reuters in an interview.