Ancelotti has a deal with Real to 2026, though his future is clouded given the team's rollercoaster season so far.
Okdiario's chief pundit Eduardo Inda, while speaking on El Chiringuito, says Milan have made contact with their former coach about a return.
Inda revealed: "I am told that the CEO of Milan has addressed his former friend Carlo Ancelotti.
"He has told him that if he leaves Real Madrid he has the doors of Milan open in the final stretch of his career, where he was a player and also a coach.
"The offer holds in case he does not continue as coach of Real Madrid next season."
Milan coach Sergio Conceicao's contract carries a break clause should they fail to finish in the top four this season. The Rossonero currently sit in seventh place on the table.