The club faces transfer debt repayments of about €222 million this year.
Manchester United are reportedly aiming to clear €1.4 million a week from their wage bill this summer to fund future signings.
Departures including Casemiro, Jadon Sancho, Marcus Rashford, Rasmus Hojlund and Andre Onana could free up more than 72 million annually.
Finding a replacement especially for Casemiro, is understood to be a key priority.
The club also faces transfer debt repayments of about €222 million this year.

Marketa Vondrousova Appeals Four Year Ban From Tennis
Joe Mallon Motors Senior Ladies Football Fixtures
Irish Women's Four Team Secure Spot In The World Rowing Championships Semi Final
Tuesday Morning Sports Update
Gibraltar FA Latest To Pull Its Support For Gianni Infantino
Fulham And Chelsea Face Off In A West London Derby Tonight
Troy Parrott To Make Real Betis Debut Tomorrow
Monday Morning Sports Update