The 34-year-old Ivorianâ€™s contract is due to finish in the summer and talks were due to be held by the player and the club in the coming weeks.
"We [me and my team-mates] will no longer be together next season," Drogba said in quotes attributed to France Football magazine.
"As I decided to leave, I wanted to tell them straight in the eye. Except that I could not do it. They made me crack.
"Even though it's been three years since I said I wanted to leave, I find it hard to admit that it's over with this club - especially as I did not feel like this.
"But I could not see myself sitting on the bench to watch others play when the club plans to set up a new team.
"So that's it - I am preparing for my leap into the unknown. It's going to be another adventure."