Maurizio Arrivabene says it was his decision to oust Kimi Raikkonen.
Some believe the shake-up, with Raikkonen to be replaced by young charger Charles Leclerc next year, was actually decided by Ferrari president Sergio Marchionne prior to his death in July.
'I was the one who made it'
But Ferrari team boss Arrivabene told Sky: "It was my decision."
He said he had the backing of Ferrari's new upper management including Louis Camilleri and John Elkann.
"They understood the logic behind the decision, but I was the one who made it," Arrivabene insisted.
The Italian said it was hard to tell 39-year-old Raikkonen the news.
"For me, Kimi is also a friend, so you can imagine how heartbreaking it was to tell him. Drivers are just as human as I am, but in situations like that they are treated as professionals," said Arrivabene.