E.ON agreed with RWE a year ago to split up the assets of RWE's Innogy unit, a transaction that will turn E.ON into one of Europe's biggest energy grid and power retail groups.

The company expects to close the transaction by the end of the year and will expand its supervisory board by six seats to 20 members, including three additional shareholder representatives, to better manage the integration.

"For a successful integration, we will also need experience and know-how from Innogy on the supervisory board of the new E.ON, on both the shareholders' and employees' side," E.ON Supervisory Board Chairman Karl-Ludwig Kley said.

Three additional employee representatives will be added to the board, with the seats taken by Innogy employees, E.ON said. Shareholders will vote on the proposal at E.ON's annual general meeting on May 14.

In 2023, E.ON, which is scheduled to hold its annual press conference on Wednesday, plans to cut the number of seats on its supervisory board to 12.

(Reporting by Christoph Steitz; Editing by Jan Harvey)