Ahead of final free practice for the Japanese Grand Prix in Suzuka, the team announced Vettel’s departure after being informed of the decision on Friday night.
The four-time reigning world champion has not won a race this season – his worst season in the sport – and seen team-mate Daniel Ricciardo impress since stepping up from Toro Rosso this season, winning three races.
“Red Bull and I have had an incredible run together,” he said. “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. 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.”
The 27-year-old, who has won 38 races from his six seasons in Red Bull’s F1 team also admitted it was a tough day as the decision was made public with the team naming his successor as current Toro Rosso driver Dani Kvyat.
“Even though it’s not the easiest decision to live with, you have to listen to your heart and go in your direction,” Vettel added.
“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.”
With the future of several drivers the talk of the paddock, Vettel again struggled to get the best from the RB10 in qualifying as he finished in P9 with a time of 1m34.432 almost two seconds off pole sitter Nico Rosberg’s time of 1m32.506, with Ricciardo in P6 with a time of 1m34.075.
“I wasn’t entirely happy with that qualifying, we lacked some running his morning but I wasn’t able to go with the track and was on the back foot,” Vettel said.
“I struggled a bit on corners that I normally love, so it’s not easy, but tomorrow we still have a chance if it rains, if it doesn’t then it’s tougher from where we start but we will see.”
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