Mr Diller has been asked by Vivendi Universal's top executive, Jean-Rene Fourtou, to play the part of interim co-CEO of the ailing Paris-based company as it tries to sort out its identity and finances, according to sources close to Mr Diller and the company. Already chairman of Vivendi Universal Entertainment, Mr Diller is being handed the bigger corporate role at a time when the French conglomerate is trying to ease investor concerns about the stability and competence of its management team.