Dick Advocaat has informed Sunderland that he is not interested in becoming their head coach on a full-time basis.
The Dutchman has decided to call time on his career in management, saying that "the decision was always Sunderland or nobody".
He took over as interim head coach after the dismissal of Gus Poyet in March and helped the Black Cats to a 16th-place finish and Premier League safety.
"At certain moments in your life you have to make a decision and I am almost 68 years old now. A number of clubs contacted me but the decision was always Sunderland or nobody," he told the club website.
"I would like to thank the chairman (Ellis Short), Lee [Congerton, sporting director], the staff and of course the fans. We gave everything in our time there and achieved what we set out to. Sunderland has been one of the highlights of my career."
Advocaat brings down the curtain on a 28-year managerial career that included stints in charge of the Netherlands national team, PSV Eindhoven and Rangers.
Black Cats chairman Short added: "Although I am extremely disappointed, I understand and absolutely respect his decision. In his brief time here he made a real impact and lifted the club with his experience and enthusiasm. We will always be grateful to him for what he achieved."
Sunderland will now begin their search for a new head coach, and current Watford boss Slavisa Jokanovic has been linked with the post.
