Despite having a contract at the Westfalenstadion until 2022, Sancho is expected to sign for a new club during the summer transfer window.
Earlier this month, it was suggested that the England international, formerly of Manchester City, had identified Manchester United as his preferred destination.
However, according to Sky Sports' Kaveh Solhekol, the North-West giants need to secure a return to the Champions League before being able to complete a deal.
Solhekol suggests that Liverpool will be the frontrunners to sign the 19-year-old should United miss out on European football's top table for another campaign.
Sancho has made seven appearances in this season's competition, contributing two goals and two assists.