The German utility RWE said Thursday that Chief Executive Harry Roels would resign at the end of the month, four months earlier than planned.
The Essen-based provider of electricity, water and natural gas said its supervisory board approved the appointment of steel company executive Juergen Grossmann, 55, to replace Roels, who had been CEO since February 2003.
Grossmann is the head of German steelmaker Georgsmarienhuette GmbH. He bought the company in the 1990s and pulled it back from the brink of bankruptcy.
He was already a member of RWE's economic advisory board.
No reason was given for the early departure. RWE said Roels, 59, had offered the supervisory board, the U.S. equivalent of a board of directors, "an early termination" of his appointment. Originally, the company said Roels was set to leave at the end of January 2008.
Board Chairman Thomas Fischer praised Roels' work during his time as CEO.
"The term in office of Mr. Harry Roels with his extensive international experience has been an extremely successful period for the RWE Group," he said. "The strategic realignment and long-term improvement of the group's financial situation are tremendous corporate achievements."
RWE is one of Germany's biggest suppliers of electricity and operates utilities in Britain and owns oil and gas exploration companies, energy trading firms and coal mining operations. It provides electricity to 20 million customers.
Shares of RWE were up more nearly 1.2% to 86.72 euros ($121.19) in Frankfurt trading.