The 22-year-old has made 52 appearances for the Magpies after the defender completed a £3.5m move to St James’ Park from Internazionale, signing a five-year deal.
The 18-time Serie A champions are looking to rebuild their squad after seeing many of their veteran stars depart last summer, including Clarence Seedorf.
Berlusconi, who assumed control of the San Siro outfit in 1986, admitted Milan are interested in Newcastle’s Santon and Roma’s Mattia Destro.
“We will build a team with young players who can help AC Milan to be a leader in Italy and in Europe,” Berlusconi told Mediaset Sport.
“Davide Santon and Destro? I gave my world to [Milan vice-president] Adriano Galliani I wouldn’t reveal any names, but these are players we like.”
Milan are 14 points behind Serie A leaders Juventus, prompting speculation about Massimiliano Allegri’s position at the club.
But Berlusconi insisted he has a “great relationship” with the Milan manager, but conceded results most improve in 2013.
“Allegri? I have a great relationship with Allegri, a relationship of friendship and cordiality,” Berlsuconi added.
“He can leave? Much depends on the results that he will obtain.”
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