Bortoleto said: “This is one of the most exciting projects in motorsport, if not in all of sports.
“Beyond simply being a member, I aim to grow with this ambitious project and reach the pinnacle of motorsport.
“Mattia was super confident about the Audi project and how I could develop as a driver as well.
“I see a lot myself in this project. I needed to convince him much more than he needed to convince me, but I identified a lot (with it).”
Binotto, who was Ferrari team principal from 2019-22, said last month that turning Sauber into a winning team under the Audi name was “not only climbing a big mountain, it’s climbing Everest”.
He said in a video released by Sauber on Wednesday: “It will take a few seasons to become a a competitive team. Our objective will be to be aiming to fight for a championship in 2030, and even that is very ambitious.”
The team released separate statements thanking them for their work.
Bottas, who made his debut in F1 for Williams in 2013 and won 10 races in his five years at Mercedes as team-mate to Lewis Hamilton from 2017-21, said: “A situation like this is never easy for anyone. But after all the good and in-depth discussions we had in the past weeks, we realised that the conditions to grow this project together were not met.
“These past years with the team have been an incredible journey, full of growth, challenges, and unforgettable moments.
“Though it’s time to move on, I’ll always carry a piece of this team with me, and I look forward to seeing what the future holds for us both.”
Bortoleto gives Brazil a full-time presence on the F1 grid since Felipe Massa left the sport at the end of 2017.
The country is one of the most successful in F1, with former drivers including multiple world champions Emerson Fittipaldi, Nelson Piquet and Ayrton Senna.
