After the passing of Niki Lauda this week, Sebastian Vettel has opened up on why chose to send a written note to the Austrian while he was recovering from a lung transplant last year.Vettel was a huge admirer of Lauda and has claimed the kind gesture was out of respect for 'what he’s achieved, the person he is, what he’s done for the sport'.“I heard he was not doing well and not doing well for a while, and he wasn’t in the mood to pick up the phone or the state to talk over the phone,” said Vettel, per Motorsport.“You think what would you appreciate if you were in that situation? Just reading a little note is a nice thing.“For me it was a no-brainer and a sign of respect.”

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Vettel, who has previously spoken of his interest in the history of the sport and his team, went on to speak of the insight Lauda gave him, saying it was a 'privilege' to have the opportunity 'to ask him all sorts of things: how the cars were, how the time was with Ferrari, how was Enzo Ferrari?'.

Despite going on to become the non-executive chairman at rivals, Mercedes, Vettel praised Lauda for being someone everyone could talk to.

“I feel privileged I had the chance to not just know him, but chat with him regularly, enjoy jokes with him and so on,” added Vettel.

“His sense of humour was very straight. Sometimes you couldn’t tell if it was just a joke or just a statement. I certainly enjoyed that. 

“You don’t come across people like him very often, not just in F1 but in general. He was a unique person.”

The four-time World Champion will pay tribute to Lauda at this weekend's Monaco GP, wearing a specially designed helmet, displaying the classic look Lauda carried throughout his career.

Ferrari will also carry the name of late Austrian racer on their cars, along with others on this weekend's grid.