Thorgan Hazard has told Borussia Monchengladbach he wants to leave this summer amid reported interest from Borussia and Dortmund.
Sporting director Max Eberl revealed the news on Monday, with Belgium international Hazard - brother of Chelsea star Eden - heavily linked with a move to Signal Iduna Park.
Monchengladbach had hoped to keep the talented winger, whose contract expires in 2020, but Eberl says Hazard has made it clear he wants a fresh challenge.
The 26-year-old has scored nine goals in 27 Bundesliga matches this season, helping the German side climb to fifth in the Bundesliga table.
Despite Hazard making his mind up on a summer move, Eberl insists that Monchengladbach will only sell him when his valuation is met.
He told the club's website: 'We made our intentions to extend Thorgan's contract clear a while back now, but he hasn't reciprocated that interest.
'He has now told us that he doesn't want to extend his contract and instead wants to take the next step in his career by leaving the club.
'However, he still has a contract with us until 2020 and there is no release clause.
'Interested parties have to offer us a transfer fee that recognises his worth as an exceptional Bundesliga forward and a regular feature in one of the best national teams in the world.
'If it ends up being the case that Thorgan leaves us, then we will do what we've done well in the last few years - we will take the money we make from the transfer and use it to buy more exciting players for our team.'