As the director of business development, he will help set up and co-ordinate a new business board involving Havas divisional directors.
Havas said the move was part of its re-organisation plan and drive to strengthen its management team.
The group recently announced a major restructure and hundreds of job losses as it struggles to get back on course after a first half-year net loss of £41 million.
However, it received a boost last month by beating Publicis and WPP to land the £120 million account of the French supermarket chain, Carrefour.
The appointment follows that of Jim Heekin, the ousted chairman of McCann-Erickson Worldwide, who was last week named president and chief operating officer of the Havas-owned Euro RSCG.
De Yturbe stepped down as the deputy president of the Bates network's Cordiant parent in March. His departure followed shortly after that of the chief executive, Michael Bungey, who was forced to bow to shareholder pressure over Cordiant's poor performance.
Hit by a tumbling share price and devastating account losses, Cordiant was acquired by WPP In July.
De Yturbe said at the time of his departure that he was eager for a change after ten years at Bates. "I wanted to see and do something different," he added.
A member of one of France's wealthiest families, de Yturbe joined Bates in 1993 as chief executive of its French operation. He became European chairman two years later and was named president of Bates Worldwide in December 1999. He took over as Bungey's deputy at Cordiant in March 2002.