The Red Devils continue to be linked with the England international, although it has been suggested that the financial impact of the coronavirus outbreak could see the proposed deal fall through.
Sancho has been left on the bench for BVB's three Bundesliga matches since the action resumed in the middle of May amid the speculation surrounding his future.
The 20-year-old has been in terrific form for Lucien Favre's side during the 2019-20 campaign, though, contributing 17 goals and 20 assists in 38 appearances in all competitions.
According to 90min, despite the financial issues facing clubs this summer, United are still confident of securing Sancho's signature in time for the 2020-21 campaign.
The report claims that Dortmund are attempting to agree a new deal with the Englishman which will allow him to leave next summer, but the Red Devils want to sign him in the coming months.
Chelsea are also still thought to be interested in the former Manchester City youngster.