Long-time finance director Riaan Koppeschaar, who has been acting CEO since December, will continue in the role while the company looks for a permanent replacement, Exxaro said in a statement.

"We have accepted the resignation of Dr. Tsengwa", Exxaro board Chairperson Geoffrey Qhena said in the statement.

"We will initiate an expedited process to identify and appoint a new CEO who will continue to drive growth, excellence, and innovation within our business."

Tsengwa's successor will be tasked with leading Exxaro, a major supplier of thermal coal to SA's power plants, as it searches for clean energy minerals, mainly copper and manganese, in its quest to diversify away from polluting coal.

--Reuters--