"Milan's problem is economic," Ibra declared in a press conference on international duty with Sweden.
"There is no money to buy five players, or even the ones we need. We made a couple of signings, maybe there will be a third."
Riccardo Montolivo and Bakaye Traoré have both been snapped up on free transfers.
"I guess it's true that the longer you play together, the more you improve. Just look at Chelsea, who won the Champions League although they were not the strongest team."