Chief executive Adriano Galliani has revealed that AC Milan will complete the re-signing of Kevin-Prince Boateng next month.
The Ghana international joined Milan in 2010 from Portsmouth and he went on to spend three years at San Siro prior to his switch to Schalke 04.
He has since gone on to make over 50 appearances for the Bundesliga outfit, but none of those have come this season following a dispute with club officials.
The 28-year-old has recently spent time training with Milan, whom he will now rejoin on a free transfer.
"On January 4 we will register Boateng's contract with the Lega Serie A and he will be available for selection," Galliani told Sky Italia.
Boateng scored 17 goals from his 100 outings for the Rossoneri during his first stint in Italy.