Maurizio Sarri has reportedly told Gary Cahill he can leave Chelsea in January, according to the Sun.
The 32-year-old has played just one Premier League game under Sarri when he came off the bench against West Ham.
As Calicomercato reported before, AC Milan are considering a swoop when the transfer window opens as they are in desperate need of a fresh player.
A loan move in the New Year appears the most likely option, with Milan's senior players believed to favour a move for Cahill's team-mate Andreas Christensen.