The 30-year-old has slipped to fourth choice in the Old Trafford behind Wayne Rooney, Javier Hernandez and Danny Welbeck, which has added to speculation over the Bulgarian’s future under boss Sir Alex Ferguson.
"We're not just looking at Berbatov; we're interested in a number of players," Unal told Hurriyet.
"Yes, we're thinking of forwards, but now is far too early.
"We can only get in contact and decide at the end of December, when the time comes. We have four or five players in mind.
"But we can't say that we want to buy any one player because we have not decided yet."