The Netherlands international refused to take a paycut earlier this year, and has so far failed to reach an agreement with the club over a new contract.
Coach Andrea Stramaccioni opened the door for Sneijder to return to the first team, but the midfielder has now confirmed that the player's relationship with the club has deteriorated beyond repair.
"Clearly it’s better for everyone if I leave in January," the former Ajax man told De Telegraaf.
"If that doesn’t happen, then I will stay. I have a contract until the end of June 2015 with Inter."
Sneijder also confessed that it would be a privilege to wear the Dutch captain’s armband once more, and hopes he can return to the national set-up soon.
"It would be a great honour to wear it again," he said. "I have kept in contact with [head coach] Louis van Gaal over the last few months.
"I saw several players try to pass the buck after the Euros, leaking stories to the media about tension in the locker room. It seemed like that to me at times, but the atmosphere wasn’t that bad."