Africa-focused Tullow Oil Plc named Phuthuma Nhleko, former boss of South African telecom major MTN Group, as chairman-designate on Monday, a role that he also holds at the Johannesburg Stock Exchange Ltd.
Nhleko, a South African national, will replace Tullow's Chairwoman Dorothy Thompson who is retiring by this year-end.
Tullow earlier this year emerged from a financial overhaul, with a $1.8 billion bond and a new business plan under top boss Rahul Dhir.
"Phuthuma will play an important part in supporting Tullow's ambitions to be a partner of choice for governments and our industry peers, as the African oil and gas sector evolves over the coming decade," said Thompson.
Nhleko, currently chairman-designate of JSE, was supposed to take on the role of chairman of the bourse from next year. JSE did not immediately respond to a request for comment.
"I am very pleased to have been appointed as Chairman-designate of Tullow, a company I have followed with much interest since its inception," Nhleko said in a statement.
"I believe Tullow is uniquely placed to develop the oil and gas resources of its host countries efficiently and safely while minimizing its environmental impact."
(Reporting by Yadarisa Shabong in Bengaluru; Editing by Anil D'Silva and Rashmi Aich)