United are keen to strengthen the right-hand side of their attack this summer, but with financial uncertainty due to the implications of Covid-19, the club are not willing to pay over the odds for any transfer.
Goal can confirm that the Bundesliga outfit want €120 million (£108m/$142m) for the England international, and the two clubs were said to be far apart on their negotiations last week despite claims an agreement had been reached.
United were always prepared to walk away from the deal and pursue other targets if a price could not be agreed upon, one of which is Bayern Munich winger Kingsley Coman.
Dortmund set their own unofficial deadline of August 10 on the deal, and have been insistent that if a transfer was not confirmed by that date then Sancho would be staying.
It is understood United were not willing to be bound by the “unrealistic” deadline and were not rushing to get the deal done by that date.
It is also understood that Sancho, who has spent the past two years in the Bundesliga, wants a move to Old Trafford, and the latest comments from Zorc show he will have to force a transfer through if he really wants to make the switch back to England.
United have yet to conclude any business in the summer transfer window but are understood to have plans for at least a couple of deals before it shuts in October.
Solskjaer’s side play FC Copenhagen in Cologne on Monday night for a place in the Europa League semi-finals.