He claims that in order to play in a new league, he tried to sign on with Barca.
The 33-year-old, who was entering the final year of his contract at the Allianz Arena, would cost both clubs €45 million.
With this move, Lewandowski will finish his eight-year association with Bayern.
“I had known for a very long time that I wanted to play in a league other than the Bundesliga.
He told Bild, “I wanted to live somewhere else again, to experience something new with my family.
“But I must stress: It was the hardest choice I’ve ever had to make.