"Bayern, as opposed to some reports, has no contract with Robert Lewandowski," the Bavarian Champions League semi-finalists said in a brief statement.
Bayern, who beat Barcelona 4-0 this week in their Champions League semi-final first leg did not say whether talks were ongoing with the player's representatives.
Bayern stunned Dortmund fans a day before their team crushed Real Madrid 4-1 in the Champions League semi-final first leg on Wednesday with the announcement of a deal with Dortmund attacking midfielder Mario Gotze worth a reported 37 million euros.
Bundesliga top scorer Lewandowski, who netted all four goals for Dortmund against Real, has refused to sign a contract extension beyond 2014 and could leave as early as this summer.
He, unlike Gotze, does not have a buy-out clause in his contract and could be forced to stay on.
"Until today we have no offer for him. He has a contract until 2014 without a buy-out clause," Dortmund boss Hans-Joachim Watzke told Bild newspaper.
Representatives of the players had said on Thursday the Poland international would not stay on in Dortmund but the 24-year-old has yet to comment on his future.
Lewandowski's long-speculated move to Bayern was fanned by the signing of former Barcelona coach Pep Guardiola for next season.
Guardiola, who won more than a dozen titles with the Spanish club in a four-year spell before taking a year out, was also cited by Dortmund as youth product Goetze's reason for a sudden change of heart and in favour of their arch-rivals.
The Bavarians, who secured their first silverware since 2010 when they won the Bundesliga title two weeks ago, are eager to dominate in the Champions League after losing the 2010 and 2012 finals.
