Borussia Dortmund chief executive Hans-Joachim Watzke has confirmed that Robert Lewandowski's wages have been increased to reflect the striker's "sporting value".

Lewandowski has less than a year left to run his current contract at Dortmund, with the Polish striker making no secret of his desire to leave next summer, preferably for Bayern Munich.

Watzke revealed that Dortmund have been in talks over Lewandowski's salary with the Pole's agent for a couple of months, with an agreement reached this week to improve his earnings.

He told Bild: "We have been looking into the situation of Robert together with his agent.

"I am not here to tell details, but this has always been the case and will remain so. Just like it usually is in this business. One result of this [the talks] is, of course, that we have updated the wages of Robert.

"We had planned this months ago and Robert's wages are now up to his sporting value."

The 24-year-old has played in both of Dortmund's first two Bundesliga matches this season, scoring once in a 4-0 win at Augsburg on the opening day.