The Red Devils have made two signings during this summer's window, bringing in Joshua Zirkzee from Bologna and Leny Yoro from Lille, but Erik ten Hag's side are targeting further acquisitions.
Paris Saint-Germain's Manuel Ugarte is said to be the club's leading midfield target, while Man United are believed to still be hoping to sign Matthijs de Ligt from Bayern Munich.
According to ESPN, the Red Devils want at least three more signings - a central midfielder, another centre-back and a right-back - but outgoings will need to occur to balance the books.
The report claims that the club are willing to listen to offers for Victor Lindelof, Aaron Wan-Bissaka and Christian Eriksen, who have all been named in the squad for the pre-season tour of the United States.
Maguire, Sancho among those 'available' for transfer
Meanwhile, any serious offers for Harry Maguire, Scott McTominay, Antony and Jadon Sancho will allegedly be considered, with all four available for the right price.
Maguire, McTominay, Antony and Sancho are also heading to the United States, with Man United preparing to play three matches against Arsenal, Real Betis and Liverpool.
However, there is an acceptance that more players will have to depart this summer if the Red Devils are to bring in a further three players before the market closes.
Sancho has patched-up his relationship with Ten Hag, with the forward involved against Rangers on Saturday, but Paris Saint-Germain are being heavily linked with the Englishman, and he could potentially depart if an offer of around £40m is submitted for his services.
Which players have already left Man United this summer?
Mason Greenwood has been the team's biggest exit, with the 22-year-old completing a permanent move to Marseille after spending the 2023-24 campaign on loan at Getafe.
Willy Kambwala, Alvaro Fernandez and Donny van de Beek have also been sold this summer, while Omari Forson left at the end of June to complete a move to Italian side Monza.
Raphael Varane and Anthony Martial also saw their contracts expire at the end of last month, while Brandon Williams and Shola Shoretire were not offered new deals.
Sofyan Amrabat's loan deal from Fiorentina has expired, although it is understood that Man United are in talks over the possibility of a return to Old Trafford on a permanent basis.