The 22-year-old, who scored 19 goals in 31 league starts this season, is widely expected to leave the club this summer with Middlesbrough, Wigan and Celtic among the clubs rumoured to be interested.
But, despite admitting the club have received offers for the player, Wharton insists a move is not inevitable.
"There are four or five clubs showing an interest in Gary," Wharton told the Scunthorpe Telegraph. "We have had some bids too but these have been turned down.
"If someone comes in with an offer we cannot refuse, and providing it is a club that Gary wants to go to, then something might happen. But I cannot second guess what will happen.
"I am not resigned to losing Gary this summer - but I would not be surprised if a transfer does happen."