The Argentine impressed during a loan spell at the club last season, scoring eight goals in 33 Serie A appearances.
Verona only tied down his permanent signing from Porto for €15 million in May, but a host of clubs, including Milan and Juventus, reportedly have their eye on the 21-year-old.
And Mandorlini accepts his star man will now leave the club, also revealing fellow loan signing Romulo is unlikely to extend his stay.
"I don't know where Iturbe will go, but I wish him all the best," Mandorlini is quoted as telling Sky Sport Italia.
"He has grown so much over the past year. He can play for any club. Romulo also did well with us.
"We are losing these players, but want to do well next season and repeat the excellent results of this campaign."
Juve have been linked with a deal that could see Fabio Quagliarella going the other way.
When asked for his opinion of the experienced striker, Mandorlini added: "He is a player who has done very well in his career, but I don't know whether he's suited to Verona's finances.
"In technical terms he is a strong player who proved his worth over the years."
