Juventus, Manchester United and Manchester City have been warned off making a move for Gianluigi Donnarumma by AC Milan president Silvio Berlusconi.
Donnarumma emerged from the Milan youth set-up last season and has firmly established himself as number one, earning acclaim as one of the most exciting prospects in European football.
Donnarumma's performances have seen him compared to Buffon - who played his 1000th match in Italy's World Cup qualifying win over Albania on Friday - and Europe's top clubs have expressed their interest in acquiring his services.
"For us he is not for sale," Berlusconi told La Verita."Donnarumma is part of the Milan heritage.
"He is a splendid product of our youth academy, he feels a strong attachment to the club and to the Rossoneri colours.
"He is incredible for us."
