The 33-year-old sees his current deal with the Bavarians expire in June 2023, and with no extension being agreed, interest from Barcelona has reportedly been growing in recent weeks.
Lewandowski has said to have informed the club in recent days of his decision against signing a new contract, although the Bayern hierarchy have continued to insist that the Poland international would be staying at the club for another year.
However, the former Borussia Dortmund man has revealed his decision publicly following Bayern's final game of the Bundesliga season at Wolfsburg on Saturday.
Speaking after the 2-2 draw at the Volkswagen Arena, Lewandowski told Sky: "I won't sign a new contract. We have to find the best solution for both sides. I told the club that if an offer comes in, then we have to think about it - also for the club."
Lewandowski netted his 50th goal of the campaign for the Bavarians during that game, taking his tally to 344 goals in 375 appearances since joining in 2014.
In addition to his public comment after the draw on Saturday, the striker also appeared to wave goodbye to the visiting Bayern fans at the Volkswagen Arena, having helped the side to its 10th successive Bundesliga title this season. body check tags ::