The Rossoneri have overtaken rivals Inter in the race to sign the Dutch midfielder but differences remain regarding the two clubs' valuation of the tough-tackling player
The Premier League champions value the Dutch midfielder, whose contract is set to expire at the end of the season, at around €8.2 million, but the Rossoneri are currently willing to pay only €3.7-€5m for his signature.
Milan have secured deals to bring strikers Bojan Krkic and M'Baye Niang to San Siro and regard De Jong as an ideal replacement for his compatriot Mark van Bommel, who joined PSV this summer.
Last week, Massimiliano Allegri's team overtook rivals Inter in the race to sign the 27-year-old, with the Nerazzurri having sealed the transfer of Uruguayan midfielder Walter Gargano from Napoli.
Milan chief executive Adriano Galliani is considering a variety of bonuses and incentives that could balance a potential offer to De Jong, who is expected to command a salary in excess of €3.8m per season if he does complete a move to Italy.
A move for Real Madrid midfielder Lassana Diarra, in addition to interest in Kaka, has been abandoned, with the former Arsenal and Chelsea player set to join Fenerbahce for €5.5m per season for three years.
Djamel Mesbah, Edoardo Pazzagli and Adria Carmona, meanwhile, could leave the Italian club as they look to trim their squad numbers.