The Danish international is on a season long loan from Arsene Wenger's Arsenal side but a permanent deal is not a forgone conclusion. O'Neill will have his own transfer targets in mind when the summer comes and whether he wants to splash out on Bendtner, who reportedly earns £50,000 a week, on a permanent basis remains to be seen.
Meanwhile the player himself has not decided on his own future, Bendtner has made it clear he has no intention of returning to play for Arsenal again but he has also said in the past that he would only join a club where they have qualified for the Champions League, that would rule out Sunderland.
O'Neill told the Daily Mail: "His future? I really don't know. I've not even discussed it with him.
"But I think he realises it's a big season for him. He's been sent out on loan to us from Arsenal who have decided not to use him this season. Perhaps that would have been a blow to his confidence, although perhaps not."