Luca di Montezemolo will quit as Fiat chairman, the company has announced in a statement.
However, di Montezemolo will stay on Fiat Group's board and will remain chairman of Ferrari.
The statement said Montezemolo is stepping down on the eve of the presentation of Fiat Group's 2010-2014 business plan because he has "completed the assignment given to him" when he was appointed chairman in May 2004.
However, Automotive News is reporting that di Montezemolo is quitting the post because he does not agree with CEO Sergio Marchionne's future strategy for Fiat. It also says di Montezemolo, 62, is likely to look for a career in politics now.
Marchionne is scheduled to announce the automaker's new five-year business plan tomorrow.