The £30.75million forward has found first-team places difficult to come by since being left out of the United squad for last season's Champions League final defeat to Barcelona.
And, on the eve of a last-16 Europa League second leg tie with Athletic Bilbao, Ferguson confirmed the Bulgarian is set to leave in the summer.
"His concern is not getting first-team football," said Ferguson. "At 31, he is looking at first-team football. It is difficult for me to guarantee that so it could lead to him looking elsewhere."
Berbatov's contract is due to expire in the summer.
However, rather than let the former Tottenham man leave for nothing at the end of the season, they will trigger a one-way clause to extend the deal for a further year.
That would mean United would get a fee for the player, who was linked with former club Bayer Leverkusen during the January transfer window.
However, the Red Devils hierarchy know they would get nothing like the mammoth sum they paid for the striker, whom Ferguson had such high hopes for when he arrived but has never quite managed to fulfil them, despite ending last season as the joint Golden Boot winner.
"We will be taking up the option on his contract but, having had chats with him, I understand he wants to get first-team football," said Ferguson. "It is something we need to consider at the end of the season. For a player of his age and his ability it is disappointing for him that he is not getting first-team football.
"We will look at the end of the season but until then, he remains at United."
Source: PA
Source: PA