The chief executive of ArcelorMittal's South African unit said on Monday he was stepping down, after less than two years at the helm, to pursue other interests.
The company, a unit of the world's largest steel maker, is facing tough times due to sinking steel prices, rising costs and cheap imports, did not name a successor.
Its shares fell more than 5 percent on news of Paul O'Flaherty's departure.
In a statement, the company said O'Flaherty will join the company's board as a non-executive director, after he officially resigns as CEO on Feb. 12, to ensure continuity and roll out strategy.
"The time has come for me to step down as the CEO as I wish to pursue other interests," O'Flaherty said in the same statement.
Steel companies around the world are grappling with a global supply glut but South African producers are under even more pressure as cheap Chinese imports threaten demand and hammer margins.
O'Flaherty was appointed in July 2014.