Doku, who will be eligible to make his debut at Sheffield United on Saturday, said: “This is a great day for me, both personally and professionally. Manchester City are the best team in world football, so to be joining them is something very special for me and my family.
“I am a young player with so much learning and improving to do. Working with Pep and his staff, and playing alongside these work-class players, will make me a much better player. I feel sure of that.”
“Watching City last season was amazing. To win the treble is the hardest thing in football and they did it. You cannot imagine how exciting it is to be joining this team. I cannot wait to get started. Hopefully I can make the fans happy.”
Director of Football Txiki Begiristain added: “Jeremy is a very exciting young player and I’m so pleased he’s joining us.
“In terms of raw attributes, he has everything a winger needs. He has outstanding pace and he is exceptional in one-on-one situations.
“I honestly believe working with Pep and the technical staff here at City will see him develop into a world-class attacking talent.”
City also sold defender Aymeric Laporte to Al-Nassr for £23.5m on Thursday while they are considering whether to raise their bid for Wolves midfielder Matheus Nunes.