Michael Zorc insists that Sancho will not be leaving Signal Iduna Park after United failed to meet their €120m asking price before their deadline of 10 August.
Despite this public stance, negotiations have continued but United are yet to meet Dortmund's demands, which the Old Trafford club believe are unrealistic.
In a press conference on Friday afternoon, Zorc maintained that Dortmund's position had not changed and that there would be no further developments in the coming days.
"Of course we communicated with Manchester United in the past," Zorc said.
"But everything there is to tell on this matter from our end has already been said. And that won't change over the next three days."