Sancho, who rejoined Borussia Dortmund on loan last season and scored in the Europa League final defeat to Tottenham Hotspur, is expected to leave United permanently when his deal expires.
However, United's option to extend it by a further year — details of which have not been publicly confirmed by the club — would allow them to command a transfer fee rather than lose him for nothing.
Bild reports that Borussia Dortmund's management, led by chief executive Lars Ricker, sporting director Ole Book and head coach Niko Kovač, are in active discussions about whether a deal makes sporting sense.
The primary concern is the financial question: if United exercise the option, Dortmund would need to pay a fee, and their preference is a free transfer or a nominal sum. "They're looking for a bargain deal," the newspaper states.
Sancho's wages represent a further complication. He earns approximately €16 million per year at Manchester United — a figure Dortmund are unlikely to match in full. United have limited appetite to cover a significant portion of his salary in any potential deal.
The hope within Dortmund's camp is that United choose not to exercise the option, as retaining Sancho on those wages without a transfer pathway serves little financial purpose.