The Swedish striker spent two seasons with the Rossoneri between 2010 and 2012, helping them to the Serie A title during his debut campaign.
He was offloaded to ambitious French outfit Paris St Germain last summer, with the Ligue 1 side one of a few sides who could afford the fee he demands and the salary he earns.
It is the financial package required to land Ibrahimovic which Galliani feels would prevent Milan from re-signing the 31-year-old.
He said: "A return for Ibrahimovic does not seem possible as his salary demands are too high.
"He is a professional. We were sad to sell him but he earns the kind of money that is not compatible with our finances.
"Would I re-sign him or Thiago Silva? The team who concedes fewer goals wins the Scudetto."