Southampton's executive director of football Les Reed has said that Morgan Schneiderlin leaves with the "sincere appreciation" of the club.
Reed told the club's website: "Morgan leaves with our sincere appreciation for his service across the past seven years.
"He has been a pivotal figure in our journey from a club in administration and playing in the third tier to one established in the Premier League and set for its first taste of European football in more than a decade.
"Even in the face of mounting transfer speculation across the past 18 months, he has conducted himself superbly and now moves on with our gratitude."
Schneiderlin joined Southampton from Strasbourg in 2008.