The Chile international is out of contract at the end of the season and will be able to leave Arsenal on a free transfer this summer.
Manchester City lead the race to sign the 29-year-old this month, and reports have claimed that the forward has already agreed terms with Pep Guardiola’s side.
But according to Sky Italia and The Guardian, United have made a last-ditch attempt to lure Sanchez to Old Trafford.
Along with a £25m bid to Arsenal, United have proposed a salary package to Sanchez which beats City’s current offer.
The report also claims that United are ready to use Henrikh Mkhitaryan as a makeweight in their deal with Arsenal, although that approach could be complicated by the midfielder’s wage demands.
Jose Mourinho is also keen on a move for Mesut Ozil, and reports last week claimed that United’s board are willing to spend £35m on signing the Germany international this month.
Like Sanchez, Ozil will also be available on a free transfer at the end of the season if he fails to extend his contract with Arsenal.
Sanchez, meanwhile, came close to joining City in the summer transfer window but Arsenal pulled the plug on a £60m deal as they were unable to sign a replacement in time.
Arsenal remain in the market for a forward who can succeed the Chilean and have reportedly held talks with Malcom’s agent over a January deal for the Bordeaux winger.
The Gunners have also been linked with Boca Juniors forward Cristian Pavon, who has a £27m release clause.
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