

Sergio Marchionne has warned Ferrari fans yet again that 2015 will be a difficult season for the outfit.

Ferrari claimed only fourth place in last year's championship and failed to win a race, while Sebastian Vettel replaced Fernando Alonso after the Spaniard opted to move to McLaren.

Speaking at the Detroit auto show on Tuesday, Marchionne refused to wade in deeper on a war of words with the Italian marque's ousted long-time president, Luca di Montezemolo.

"Unfortunately we have dropped back, but I will not argue with those who want to make a controversy," Marchionne is quoted by Italy's La Gazzetta dello Sport.

"We start behind but we will keep our heads down and try to win."

Italian-Canadian Marchionne is also chief of Fiat-Chrysler, and reportedly focused on finding strategic partnerships for the group whilst also preparing a stock market floatation for Ferrari.

"I would like to say to the fans that I will go to some grands prix," he revealed, "but we have appointed a team leader [Maurizio Arrivabene] and he will deal with the management directly."

According to the Spanish news agency EFE, Marchionne also said Ferrari has "much work to do" after a tumultuous period, and warned that improved results are likely only in the "final five or six races" of 2015.

"I'm encouraged," he said, referring to the political victory on the engine 'unfreeze' issue, "because now we have the ability to make changes during the season.

"My hope is that we will see improved performance on the track at the end of the season. I think the most interesting part of 2015 will be the last races," added Marchionne.