Milan have announced that they have accepted the resignation of Leonardo as the club's sporting director.
The former Milan player was appointed as the club's sporting director in July 2018 and was tasked with overseeing the transfer activity of I Rossoneri.
In an official statement on the club's website, Milan confirmed the news, saying: "Leonardo has today informed AC Milan of his decision to resign from his position of the Club's Sporting Director with immediate effect. AC Milan has accepted his resignation.
"The Club wishes to thank Leonardo for his important contributions in helping to take the Club forward into in a new era and wishes him all the best for his future career.
"An announcement on the appointment of a new Sporting Director will be made in due course."
Milan CEO Ivan Gazidis has also commented on the matter, stating: "Leonardo joined AC Milan in its hour of need a few short weeks before the closing of the summer transfer window.
"Under very difficult circumstances he put his heart and soul into addressing a highly complicated situation and transmitting his energy and his ambition to the team.
"I am very grateful to Leonardo for everything he has contributed to our great Club and wish him well in his future endeavours."
The news comes shortly after the announcement that manager Gennaro Gattuso would also be leaving the club days after Milan failed to qualify for the Champions League, finishing just one point outside of the top four after a dramatic final day of the season in Serie A.