Wahl is the former chief executive of the French bank Caisse d'Epargne. His appointment to the CEO role at Havas comes after Bollore failured to tempt TBWA\Worldwide chairman Jean-Marie Dru to take over from Alain de Pouzilhac as chairman and chief executive of Havas in June.
De Pouzilhac stepped down after Bollore won four seats on the Havas' board -- a move he had vocally opposed.
Bollore said that he had taken up the role to provide stability to Havas and prove that he had long-term commitment to the company, belying his reputation as a corporate raider.
"I don't need the money. I don't need power. I don't need more work. People came and said to me that you have to show that you are there for the long term, that the best commitment is for you to become the chairman."
"My plan is to have Havas independent. We are not interested in selling anything," Bollore told the Financial Times.
At a board meeting yesterday, Bollore nominated three vice-chairman for Havas: Ed Eskandarian, chief executive of Arnold Worldwide Partners; Fernando Rodes, chief executive of MPG; and Jacques Seguela, chief creative officer of Havas.
Five new managing directors have also been named: Mercedes Erra, Stephane Fouks, David Jones and Remi Babinet. Jacques Herail continues as chief financial officer.
Shares in Havas, traded on the Paris Bourse, rose by 1.35% to €4.49 this morning, following the announcement after trading had finished last night.
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