Sebastian Vettel has been with Red Bull since joining its junior team in 1998, aged 11 © Getty Images Enlarge

Helmut Marko thinks outgoing Red Bull driver Sebastian Vettel has been lured by the "myth" of Ferrari more than its ability to provide him with a competitive car right away.

Vettel and Red Bull announced they would part ways at the end of 2014 in a shock announcement at the Japanese Grand Prix and, though his destination has not been confirmed, it is widely assumed to be as Fernando Alonso's replacement at Ferrari. Marko, Red Bull's motorsport consultant, thinks Vettel has reached the stage of his career where a move was inevitable.

"Ferrari is still the name in F1," Marko told the official F1 website. "It's a myth, so every driver yearns to go there in their racing career. Sure, much of it is about illusions. Sebastian has already won [the title] four times. Now it's time for the myth. I also believe that the moment to move was ideal: Ferrari is down, and in such a situation you can dictate your conditions."

Though Marko was surprised by Vettel's revelation, which took place in the German's hotel room on Friday evening at Suzuka, he says he had a feeling the four-time champion was starting to get cold feet at Red Bull.

"I think the first suspicion that there was something brewing was after the summer break. I cannot nail it down to an occurrence, but it was a strong gut feeling. Remember this: at least two things had to come together. It was not only a case of Sebastian wanting to leave, but also of Fernando Alonso clearing the way. The more Alonso distanced himself from Ferrari the more likely it became that Seb would move.

"I warned [Red Bull owner] Dietrich [Mateschitz] that there was something coming. And this is not a love affair - this is a working relationship, and if you believe that the grass might be greener somewhere else, then you make such a decision. And again, I think that it was an ideal moment for Sebastian with the situation Ferrari is in."

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