In a statement Di Montezemolo said: "Ferrari will have an important role to play within the FCA Group in the upcoming flotation on Wall Street. This will open up a new and different phase which I feel should be spearheaded by the CEO of the Group. This is the end of an era and so I have decided to leave my position as Chairman after almost 23 marvellous and unforgettable years in addition to those spent at Enzo Ferrari’s side in the 1970s."
Marchionne in turn praised Di Montezemolo in announcing the chairman's exit from Ferrari: "As Chairman of Ferrari, he drove the company to a new level of technological and organisational excellence which also brought with it outstanding financial results. Luca and I have discussed the future of Ferrari at length. And our mutual desire to see Ferrari achieve its true potential on the track has led to misunderstandings which became clearly visible over the last weekend. I want to thank Luca for all he has done for Fiat, for Ferrari and for me personally."
The resignation comes after much speculation in the media that Di Montezemolo and Marchionne have clashed repeatedly over Ferrari's role within Fiat Chrysler.
Di Montezemolo is the brains behind Ferrari's plan to restrict output to around 7000 vehicles per year and reportedly wanted to keep running the brand as an autonomous part of the larger group. According to Automotive News, Marchionne demurred, wanting Ferrari to play an important role in the company's ambitious plans to push upmarket.
Over the weekend Di Montezemolo denied rumours that he was about to leave the company, stating his contract still had three years to run and that he would decide the time of his exit.
Marchionne publicly rebuked Di Montezemolo, telling the BBC: "I consider myself essential, of course, but I also know very well that I am at the service of this company. So to create positions, illusions that one can operate outside the rules, is talking rubbish. It's the same for him as it is for me; we serve the company. When the company has a change of plan, or if there is no longer a convergence of ideas, things change."
The Di Montzemolo era ends on October 13, the date that the merged Fiat Chrysler lists on the New York stock exchange.
Di Montezemolo initially joined Ferrari back in 1973 as an assistant to Enzo Ferrari. Following on from this Di Montezemolo became the company's sporting director (during which time he guided the Formula One team to two drivers' championships). He was also once head of public relations at Fiat and leader of Fiat's publishing arm, which includes the newspaper La Stampa.
Jobs outside of Fiat included organising Italy's hosting of the 1990 FIFA World Cup and being CEO of Cinzano. He rejoined Ferrari in 1991 as chairman and is widely credited with turning the company around. During his time at the head of Ferrari the company has seen its sales triple and its income increase tenfold. On top of his responsibilities as Ferrari's leader, Di Montzemolo also headed up Maserati from 1997 to 2005 and was chairman of Fiat between 2004 and 2010.
With Di Montzemolo at the firm's helm, Ferrari's Formula One team won eight constructors' championships and six drivers' championships, five of those by Michael Schumacher. The team, though, has hit a barren patch of late without a championship since 2008. This season the team is currently placed fourth, without a single Grand Prix to its name.
Marchionne has described recent results as "unacceptable", continuing that it was "absolutely non-negotiable" for Ferrari to win races.
Corriere della Sera and other Italian media outlets are speculating that Di Montezemolo will now be tapped to lead Italian airline Alitalia.