He is tipped to be replaced by Sean Neall, who headed the Ford business in Europe at Ogilvy & Mather from the end of 1996 until mid-1999, when he returned to the US.
Reports say that O'Malley, who is also president of the Detroit and Houston office of the advertising agency, is not leaving because of questions over his handling of the account. He joined JWT in 2001, after 13 years working at Ford's rival, car manufacturer General Motors.
Neall has a long-standing relationship with Ford. Before leaving the US for Europe, he was a senior vice-president at JWT Detroit, where he was executive management director for Ford Domestic Operations. Neal was with JWT for 12 years and managed the Ford business in the US for JWT for five years.
Ford is WPP Group's biggest client. At the end of last year, JWT recruited Saatchi & Saatchi's Tom Cordner as the worldwide creative director to work solely on the car maker's account.
Ford has advertised its cars with some striking imagery, including the ad for the Puma model starring Steve McQueen and borrowing from his film 'Bullitt'.
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