Manchester United have Sancho at the top of their transfer list for this summer, but Dortmund are not budging on their £100m asking price.
And Watzke believes no team will match their price, meaning Sancho will stay at Signal Iduna Park for next season.
"If Jadon comes up to us and says he absolutely wants to leave - which has not been the case so far - and a club wants to pay what we want, then we will discuss it," Watzke told Sport1.
"I don't think a club will pay the sum. There is also no coronavirus discount on him.
"We have left the period where we had to sell players. I don't think there will be a summer transfer.
"We have a more unusual situation next year than usual. With the exception of Achraf Hakimi [who is moving to Inter Milan] the team will stay together. That helps with development."