Manchester United rejected West Ham's request of a buyout clause being included in Jesse Lingard's loan agreement.
The England international sealed a loan move to Premier League rivals West Ham in January.
The Times says United bosses refused to insert any buyout clause into the deal that saw Lingard join the Hammers last month.
It means that if the midfielder can continue in his rich vein of form, David Moyes' side would need to negotiate a transfer fee at the end of the season.
Lingard has just one-year left on his current deal with United, so in all likelihood, a decision will need to be made on his long-term future, before the 2021/22 season kicks off.
