Rosenborg face competition for Sunderland striker Rade Prica.
Sunderland manager Ricky Sbragia told the Sunderland Echo: "There's been a lot of interest in Rade. I know Norwegian clubs are in pre-season now and, because of the way things are over there with money, no-one wants to buy him too soon.
"They'll probably be looking to make their move just before the window closes, but there has been interest in him from several Norwegian clubs.
"Rosenborg have spoken to Niall (Quinn, the chairman) about it and so have other clubs, but we might have to wait until closer to the start of their season before we get movement in that direction.
"They will probably be looking at taking him at the last minute because obviously there's going to be no question over his fitness, with him having been in training with us for so long."