Hamilton and Ferrari shocked the F1 world with news the seven-time champion will leave Mercedes in favour of the Scuderia at the end of the coming season.

Sainz is in the last year of his current contract and was in discussions about a potential renewal.

The Spaniard has been partnered with Charles Leclerc for three years, winning twice in that time.

“As you can imagine, it was not the easiest call of my life. One of the most difficult,” Vasseur confessed.

“I’m fully convinced [Carlos is] a very professional driver, that he understands that we have a long season in front of us, it’s a huge opportunity, and I think it’s also a dream to be in this situation, to have the team behind him.

“I think we had a long discussion, as you can imagine, but I will be fully supportive of Carlos.

“He is fully committed, and we know that we have to do the job together, we are together, we are professional.”

Sainz revealed he was made aware that he would not continue in red well ahead of the Hamilton announcement being made public.

However, further questions on the topic were shut down by Ferrari’s media team when he was quizzed about it at the team’s 2024 car launch.

“I think obviously a bit of a surprise like everyone in the Formula 1 world with the news,” Sainz admitted.

“From my side, you can obviously understand that I got to know the news a bit earlier than anyone else, but it’s true then I said some weeks to reflect, some weeks to prepare, and some weeks to also get ready for the car launch, for the first race of the season, so it gives you a bit of time to digest it, to take your own conclusions, and to focus on the 2024 season that is ahead.”

Vasseur subsequently moved to quash suggestions that his play for Hamilton was a reflection on Sainz.

“For the team, the opportunity of Lewis is something that you have to consider in any case,” he said.

“He’s the guy with the biggest experience, and it’s a huge opportunity for us, it’s nothing to do with Carlos.

“Carlos did a great job last year, I’m sure he well do a great job next year, he’s very professional, we have a very good personal relationship but it is like it is and we have to be focused on the future.”

Hamilton has signed a multi-year deal with Ferrari from 2025, an announcement that was well received, pushing the automaker’s market capitalisation beyond USD $7 billion.