Manchester United are reportedly struggling to offload members of the first-team squad who have been made available for transfer.
Donny van de Beek has already moved to Old Trafford in a big-money deal from Ajax, while Alex Telles and Jadon Sancho could join the Dutchman before the end of the summer window.
However, United are only likely to proceed with further high-profile additions if they are able to free up space in their squad.
According to Sky Sports News reporter Dharmesh Sheth, that is proving to be more difficult than anticipated as clubs either fail to show sufficient interest or meet the respective asking prices.
Sheth says that no formal bids have been made for Marcos Rojo, Phil Jones, Andreas Pereira or Jesse Lingard since the end of last season.
Roma are also reluctant to pay in excess of £18m for out-of-favour defender Chris Smalling.
