Lewandowski is pushing to join Barcelona.
He told BILD, "I still have one year left on my contract, which is why I asked the club for the green light for a transfer.
"I think that in the current situation, it is the best solution, especially since the club can still receive money for the transfer.
"I don't want to force anything, it's not about that. It's about looking for the best solution.
"You have to cool the emotions, I want to speak calmly and not through the media."