United want the Inter Milan winger but the two clubs haven't been able to agree a fee.
The Premier League giants don't want to pay more than £40m but the Italian outfit want closer to £50m.
But Serie A expert Gabriele Marcotti isn't sure if United need the Croatian winger.
Jose Mourinho's squad is packed full of attacking talent, and Marcotti isn't sure where Perisic fits in.
"He's certainly a very skilful player and when he's consistent, he's outstanding," he said on ESPN FC.
"He certainly hasn't always been a consistent player.
"My concern is, I just look at the players United have and I wonder how is everybody going to fit together?
"Martial is still there, you've got Mkhitaryan, you've got Juan Mata and that's before we get into (Paul) Pogba, (Ander) Herrera, guys like that.
"I don't know. If Mourinho wants another option that's fine. He's certainly busy and he has quality when he's good.
"The one thing is, you have to be confident that he's going to be consistent for you because that is a lot of money to pay for a player who used to be young and a prospect and all of a sudden is what, 27, 28 years old now.
"He isn't young anymore."
