Dortmund open to 'exceptional' offer for Hummels

"Mats Hummels has stated his wish to leave the club this summer and join Bayern Munich next season," Dortmund admitted in a statement.

Dortmund added that there was no release clause in Hummels' contract, "nor for any other player."

Hummels is under contract at the Signal Iduna Park until June 2017, but Dortmund did open the door to a move for the 27-year-old provided Bayern make "an offer worthy of the player's exceptional value".

"Up until now, Bayern have not made such an offer," Dortmund added.

Bayern chairman Karl-Heinz Rummenigge said earlier this week that the Bundesliga leaders were in negotiations with Hummels.

However, he added: "You have to respect his current contract in view of our proper relationship with Borussia Dortmund, we have to be considerate."

Hummels, a World Cup winner with Germany in 2014, started his career at Bayern but he moved to Dortmund on loan in 2008 before making the move permanent the following year.

Should he sign for Bayern for next season, Hummels would be the third big-name Dortmund star to quit Borussia for Munich in the last three years after Mario Goetze in 2013 and Robert Lewandowski in 2014.