Sebastian Vettel says Daniel Ricciardo’s success this season did not play a part in his decision to leave Red Bull Racing at the end of the year.

The four-time world champion informed the Milton Keynes squad of his impending departure late last night, with the German set to take up a seat at Ferrari.

The Red Bull team quickly announced Toro Rosso’s Daniil Kvyat as his replacement this morning.

Vettel  has been overshadowed by his Australian team-mate Ricciardo this season, with the latter recording three victories and seven podiums to hold third place in the championship standings.

The reigning world champion’s best result behind the wheel of the RB10 this season came at the Singapore Grand Prix, where he finished second to Lewis Hamilton.

Despite being outclassed by his less experienced stablemate, Vettel says his decision to leave the team that has helped him to four consecutive world titles is purely down to his want of a new challenge.

“I’m not leaving because I don’t like the team nor because I don’t like individuals nor the situation, I’m not running away from anything – it felt like the right time and the voice inside me and hunger to do something new was bigger,” said Vettel in a Red Bull statement.

“So, even though it’s not the easiest decision to live with, you have to listen to your heart and go in your direction. I feel ready and the time is right to start something new. It’s a very difficult decision after 15 years together with Red Bull, it’s a tough day.”

“Red Bull and I have had an incredible run together.

“I’m leaving a very happy place and of course it’s difficult but at some point you want to do something different.

“We had a good time and I hope we have a good final five races.”

Ricciardo said he first learned of Vettel’s decision this morning and is pleased that he had the chance to race head-to-head against the world champion.

”I was quite surprised by Sebastian’s news, I didn’t know before this morning; it’s two pretty big changes for the team, Sebastian leaving and Daniil coming in, but Seb’s done his work here at Red Bull and he feels it’s time to move on,” said Ricciardo.

“I’m glad I got one year to race with him and see how he works, I heard a lot about his work ethic before the season and it was good to see that this year and to go against him.

“Daniil’s coming in and I expect him to be quick – I know him pretty well and it should be good fun working with him.”

Despite Red Bull principal Christian Horner speaking publicly about Vettel’s Ferrari deal in the Suzuka paddock, no announcement has been forthcoming from the Scuderia.

“I am sure that very soon there will be something to say – but not right now,” said Vettel when asked of an official confirmation of his destination.

The 27-year-old shrugged off suggestions that the move will hurt his chances of winning races next season.

“At the end of the day it doesn’t really matter – as I said that it was the craving for something new; a new challenge,” he said.

“I am leaving in peace. Of course it hurts on one hand – but on the other it feels right as it means a new challenge.”

The German will start Sunday’s Japanese Grand prix from ninth on the grid with Ricciardo once again out-qualifying his team-mate in sixth.