The former Arsenal captain is ready to leave Bayer this summer for Serie A.
Calciomercato.com says while Xhaka is under contract at Bayer, the German giants are prepared to sell.
Milan, for the moment, hope to do business for around €5m for the Swiss veteran, while Bayer want €15m to part with the midfielder.
Meanwhile, Xhaka is said to have settled on a three-year deal with Milan worth around €4m-a-season.