Inter boss Antonio Conte is keen to sign Sanchez before the European transfer window closes on Monday.
If a deal goes through, Sanchez will link up with ex-United team-mate Romelu Lukaku, the striker having joined the Serie A club for £74m this summer.
However, Inter have not agreed an option to buy Sanchez at the end of the loan agreement.
United’s highest earner, Sanchez is thought to earn around £400,000 a week, a figure way outside of Inter’s current pay structure.
It has been suggested United may subsidise his salary as part of a deal and last week Inter offered to pay £150,000 of Sanchez’s weekly wages, but United wanted more.
Sanchez has had a disastrous 19 months at Old Trafford since leaving Emirates Stadium in January 2018, scoring just five times in 45 appearances.