The Serbia has been linked with a move to old.
Gianluca Di Marzio reports that United made an approach to the Series A club about the 21-year-old two days ago.
The move of the resumption of their interest in the defender, who can operate at center-back or right-back.
Fiorentina received at € 40 million bid from the Red Devils for Milenkovic in January, but turned it down as € 50m.
The Serbian featured regularly for The Viola last season, scoring three goals in 34 Serie A appearances.
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