ADELAIDE, Australia— BHP Group Ltd. said it would sell its controlling interest in two metallurgical coal mines to Stanmore Resources Ltd. for up to $1.35 billion, shifting focus to high-quality coal that it expects to be in demand as the global steel industry decarbonizes.

BHP said Stanmore will buy its 80% stake in BHP Mitsui Coal, or BMC, which operates the South Walker Creek and the Poitrel coal mines in Queensland, a coal-rich Australian state located in the northeastern part of the country. Japan’s Mitsui and Co. owns the remaining stake. The Wall Street Journal recently reported that a deal for BHP to sell the interest to Stanmore was close.