Speakman has left the club with immediate effect in a shock development.
Sunderland chairman Kyril Louis-Dreyfus said: “Kristjaan has made an important contribution to Sunderland AFC during a period of significant transition and growth, helping to rebuild the Club and restore its place in the Premier League.
"Strong foundations have been established throughout our football operations over the past five years, and that phase of redevelopment is now complete.
"As we look to the future, our focus is on building from that position of strength with clarity of direction and sustained progress. We are grateful for Kristjaan’s commitment and professionalism and wish him every success for the future.”
A club statement read: "Sunderland AFC today confirms that Sporting Director Kristjaan Speakman has left the Club with immediate effect.
"Kristjaan was a key figure during one of the most significant periods in the Club’s recent history, playing an important role in bringing Sunderland back to the Premier League.
"Appointed in December 2020, he led a comprehensive rebuild of the Club’s football operations, reshaping its recruitment and performance infrastructure and restoring competitive momentum.
"His time on Wearside included three victories at Wembley Stadium, including Sunderland’s first win at the national stadium since 1973 and two Play-Off Final wins.
"With Premier League status restored and a strengthened football leadership structure in place, the Board of Directors has made the decision to continue the Club’s journey without Kristjaan.
"Director of Football Florent Ghisolfi will continue to lead Sunderland’s sporting programme after assuming control of all football operations in July 2025."