The Italian under-21 international has struggled to nail down a first-team place since bursting onto the Premier League scene with a match-winning goal against Aston Villa in 2009, and now looks set to move on.
Macheda has had loan spells at Queens Park Rangers and Sampdoria, but failed to establish himself at either club, while the young striker has managed just 19 Premier League appearances for United in three seasons.
And his agent, Giovanni Bia, has insisted Macheda will now leave United in January, but also revealed he's unlikely to return to Italy.
"Federico at this time is not finding space, and so it is clear that in January he will go away," Bia told tuttomercatoweb.com.
"But I don't think he'll be back again in Italy because usually in January clubs are looking for players that are already ready, unless there are teams with a quiet standing which want to do long-term projects with him."
The Italian has found himself well down the pecking order at Old Trafford, with Danny Welbeck, Wayne Rooney, Robin Van Persie and Javier Hernandez blocking his path to the United first-team.
Macheda has been at Manchester United since 2007 - when he joined from the Lazio youth academy as a 16-year-old - and was highly regarded by the United youth team staff as a teenager.
The 21-year-old has made 10 appearances for Italy under-21's, and scored four goals, although he has yet to make an appearance for the full national team.