The 32-year-old, who has been tipped to join the London outfit, was reportedly in the capital on Tuesday to discuss a move to the club.
With just a few days remaining in the transfer window, Hughes has revealed that QPR are trying to conclude a deal for the Inter Milan goalkeeper.
"Sometimes when opportunities present itself you want to pursue them," Hughes said. "We're not at a point where we can actually say it's a done deal. The intention is there obviously if we can but at the moment it's not concluded.
"When you get an opportunity to possibly bring a player of the quality Julio Cesar's quality, with his playing record and his mentality, then I think you have to pursue to its conclusion.
"I think when we started the process we probably never thought there was an opportunity or chance he would be able to come here. If we are able to conclude it, we'll be delighted."
QPR have already signed a new goalkeeper in Rob Green this summer.