Insigne scored twice in the Azzurri's Coppa Italia final win over Fiorentina on Saturday and is in contention for a World Cup place.
"I don't know where these rumours come from," Fabio Andreotti said to MilanNews.it. "Milan at the moment are in a situation of standby so we haven't had any contact from them.
"Lorenzo is doing very well. The director Bigon and the President have great faith in him.
"I don't think there is any way he will be for sale. De Laurentiis wants to make him the Totti of Napoli.
"There is nothing with Milan and I categorically deny there has been any contact with the Rossoneri.
"Lorenzo is represented only by me and has been for eight years."
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