The Bavarians have so far been rebuffed in their attempts to sign the Poland international, after angering Borussia Dortmund by activating Mario Gotze's release clause in April, which saw the midfielder join their arch-rivals for £32 million on July 1.
|7/2||Robert Lewandowski is 7/2 with Paddy Power to join Manchester United
"I believe that Dortmund will be aware of that," the 57-year-old club president told Sport Bild.
"I have the impression that Watzke will stand by his words. He will have thoroughly thought about keeping Lewandowski [until 2014]."
Lewandowski has scored 54 times in 98 appearances for Klopp's side after joining Dortmund from Lech Poznan for a fee in the region of £3.8 million in 2010.
Bayern, Manchester United and Real Madrid have all been linked with the striker this summer, but it is Pep Guardiola's men who remain firm favourites to capture his signature.