Borussia Dortmund sporting director Sebastian Kehl is unsure about keeping Jadon Sancho beyond his loan.
The Manchester United winger has returned to Dortmund on a straight loan to the end of the season.
"What will happen this summer? We'll see. Realistically, the chance of Sancho playing for Dortmund next season is not very high," Kehl told Sky Deustchland.
"There was no financially feasible opportunity for us to secure a call option.
"The salary is one thing, the transfer package is another. If the player develops as we hope, other clubs will likely be active during the summer.
"He can then be a category of player that can be challenging for Borussia Dortmund in terms of feasibility."