PSG have already made an offer for the Brazilian, though it falls short of Milan's valuation.
Pastorello told Radio Sportivo: "PSG has made an important offer, but it's not enough.
"I believe that the Paris club is yet to prove it has what it takes to become a high-level team. Ancelotti's appointment is in the right direction.
"It's clear that there is an important relationship between Pato and Leonardo, but the offer they're talking about in the newspapers is still low in my opinion."