Brazil superstar Neymar completed his €222 million (A$329.66 million) move to Paris Saint-Germain on Thursday and various reports have linked France international Dembele with Camp Nou as Barca prepare to spend their world-record bounty.
Speaking to Eurosport during their coverage of the DFL-Supercup, where Dembele set up Pierre-Emerick Aubameyang's strike in a 2-2 draw before Bayern Munich prevailed 5-4 on penalties, Dortmund CEO Hans-Joachim Watzke left little room for doubt over his valuation of the 20-year-old.
Asked about a possible €100 million fee, he said: "In every case, not enough."
Watzke cited Wolfsburg's struggles since allowing Kevin De Bruyne to join Manchester City for £54.5 million (A$89.62 million) in August 2015 as an argument against accepting astronomical fees for a prized asset.
He said: "I remember Kevin de Bruyne, he was the Bundesliga's record transfer. When you see the years after, it was not the best transfer though as the team lost lots of quality."
Mounting speculation surrounding Dembele means the focus has belatedly moved on from Aubameyang, last season's Bundesliga top scorer who has been regularly touted for a move away from Signal Iduna Park over the past year.
"I think we've made clear that he will stay with us," Watzke added. "When we said that, the media wrote that he'll leave in January. No, he will definitely stay."