Ferrari president Sergio Marchionne says that Sebastian Vettel must calm down and be less agitated out on the race track if he wants to remain with the Scuderia beyond 2017.
Vettel failed to bring a win to the House of Maranello in 2016 and was out-performed by team mate Kimi Raikkonen on several occasions.
The four-time world champion was also called out this year for his numerous outbursts over the team's radio as he squawked about his peers' actions, an attitude which has led Ferrari's top brass to question the German's status with the Italian outfit.
At Ferrari's annual pre-Christmas briefing, Marchionne admitted that both Raikkonen and Vettel were under scrutiny with regard to their future.
"I admit we are looking around us for the future, by carefully analysing the others' situations," Marchionne said.
"That doesn't mean we don't have confidence in our drivers, but it's fair to say they are under scrutiny.
"I'm happy with Raikkonen's season - he will race again in 2017, but what about after that? Does he want to retire or carry on?
"With Vettel it doesn't make sense to talk about renewal now, we must first understand if he feels comfortable with us in 2017.
"We must give him a winning car, otherwise talking about the future is useless. He wants to win with us, we know that. Can we guarantee that for him?
"In exchange, he must drive with composure, be more calm, less agitated. He must think about winning on the track and beat the other cars, not about getting into personal feuds."
2016 team-by-team review: Part two
2016 team-by-team review: Part one
Andrew Green: Force India's smooth operator
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