Initiative, the incumbent on the business, has been invited to repitch for the account alongside other agencies. E.ON has made initial approaches to media agencies and is in the process of drawing up a shortlist.
Online media planning and buying, which is handled by Zed Media, is unaffected by the review, as is TBWA\London's hold on creative.
E.ON, a German energy company, dropped the Powergen brand last year in favour of its corporate name. It also ended its 18 years as the sponsor of the national weather on ITV1 as it refocused its activity on its status as official sponsor of the FA Cup.
An E.ON spokesman confirmed that a media review was taking place.