Initiative handles the mobile phone operator's media planning and buying in the UK, while MPG oversees the rest of Europe. It is understood that Orange will now allow individual markets to appoint their own media agencies.
Initiative will pitch against Carat, Mediaedge:cia, Vizeum, Walker Media and i-level, the online media incumbent, for the UK account. The winner will handle the business from 2009.
Orange's direct marketing account is held by Wunderman. A spokesman for Orange confirmed that it had "initiated contact with other agencies for some potential project work".
The news comes as the recently appointed chief executive, Tom Alexander, plans to ditch its "the future's bright" endline, created by WCRS in 1994.