City have confirmed the move, while tying the 19-year-old to a new contract.
“The talented youngster has been rewarded for his recent progress with a deal that extends until June 2020 and is now set for a first loan spell in Serie A.
“Signed in 2012, the 19-year-old French youth international became an integral part of Patrick Vieira's EDS [Elite development squad].
“Involved in every match in last term's UEFA Youth league campaign, he played every single minute of the victorious International Premier League Cup campaign, scoring in each of the three group stage fixtures.
“Everyone at the club wishes Olivier good luck in Italy."