Berbatov ended last season as United's top scorer, however the Bulgarian has found himself slipping down the Reds' pecking order, with Hernandez and Rooney the preferred choices up front.
"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."
United boss Sir Alex Ferguson's faith in his record signing has been called into question in the past but he insisted Berbatov can still make a significant contribution to the squad. He said: "Of course he's got a part to play. He's one of our squad members and they've all got a part to play."
Ferguson added: "There are a lot of games in the Premier League, Champions League, FA Cup and Carling Cup. It's an exhausting season unless you use your squad."
Source: DSG
