The defender is concerned that the club's policy to bring through younger players could mean he has to leave San Siro
The 30-year-old was used sporadically last term, making just 12 appearances all season and with the Rossoneri continuing their policy of pursuing youth, the defender says he is evaluating all possible options.
He told Milannews.it: "My desire is to end my career at Milan, but I understand that at a time like this the company has chosen to focus on young people, deciding to renew each year contracts for those over thirty.
"So one has to make their own assessments, talk with the company and try to understand the projects it has on you. It is one thing to be a fan of AC Milan, another is the profession."
Antonini then spoke about his positive relationship with Milan vice-president Adriano Galliani, but revealed he would be interested in a move abroad.
"Part of me knows there is no problem. I know that Galliani loves me as a person, because I was born and raised here and he has respect for me as a player," he added.
"Having said that I would have liked an experience abroad and I would do it, even though I understand the difficulties of moving to another country."
The left-back's deal at San Siro ends in June 2014 and a departure would bring to an end his 13-year stay at the club.