The Borussia Dortmund striker has been linked with a move to the Allianz Arena in the summer.
"Actually, it's not really necessary," he told Sky Germany. "A big transfer doesn't make any sense to me.
"When I look at the current squad, I notice that for every position Bayern have two, if not three options.
"Of course, I would take Lewandowski. However, assuring him that he's guaranteed to play could be difficult."
Bayern are currently 17 points clear at the top of the Bundesliga.