Manchester United had scouts present for AC Milan's defeat to Champions League opponents Chelsea last week.
United manager Erik ten Hag has already been identifying potential transfer targets for 2023 as he looks to make further changes to his playing squad.
Leao was scouted by United during his Champions League matches against Chelsea at Stamford Bridge and the San Siro earlier this month. Although, he did not find the net in his side's 3-0 and 2-0 defeats.
The Sun says Ten Hag is a fan of Leao, who can play across the front three, and as he enters the last 18 months of his contract, a price of £60million has been touted.
Milan have offered the striker a pay rise to £110,000 per week on a contract running for the next five years, but so far Leao has not indicated that he is going to sign the deal.
