By ESPNSTAR.com staff
The 22-year-old, who joined Marseille from fellow French Ligue 1 side Monaco last summer, is currently one of the hottest prospects in Europe and has already been linked with moves to Barcelona and Manchester United.
However, Milan have now become the first side to officially express their interest in the Cameroon international, although sporting director Ariedo Braida denies a bid will be table in the near future.
"He is a player who we have been monitoring since he was with Monaco," the Rossoneri chief told La Provence.
"At the minute, we already have six players in his role and therefore he is not top of our list.
"It's also not that easy to sign players because of asking prices."
Nonetheless, Braida did confirm Milan would be keeping a close eye on N'Koulou in the coming months.
"It would be difficult to sign him during the January transfer window, but we'll continue to watch him to understand whether he could do a good job for us in the future," he added.
Milan have had a poor start to the new season and are currently 11th in Serie A after picking up just seven points from their opening seven games.