The Athletic reported earlier on Thursday that the clubs had agreed terms on a deal for the France forward worth around £120 million, with over £100 million guaranteed.
The 23-year-old Barcola, part of France's squad at the World Cup, joined PSG in 2023 and has made 152 appearances for the European champions, scoring 39 goals and providing 37 assists.
If the move goes through, Barcola would strengthen Liverpool's attacking ranks alongside British record signing Alexander Isak, Cody Gakpo, Rio Ngumoha and Victor Munoz.
The club are seeking additional firepower after the departure of talisman Mohamed Salah, while Hugo Ekitike is sidelined with a long-term injury.
Asked about Liverpool's pursuit of Barcola and the need to add wide players, Iraola told reporters: "As you know, we are trying to sign in that position (winger), and as you know we cannot talk about players that - right now - are not ours.
"But it is evident that we are trying to improve or trying to fill that position because we don't have the numbers. I hope we can have good news soon, but we are still not there."
Gakpo's future has also been the subject of speculation, with British media linking the Netherlands forward with moves to Tottenham Hotspur and Manchester City.
The 27-year-old has been impressive in pre-season and scored in Liverpool's 2-2 draw at Newcastle United in their opener.
"Very good attitude and I hope we can keep him at that level because I think he has been very influential in our games," Iraola said of Gakpo.
"When the market is open, we have almost 30 players, you cannot guarantee anything with anyone..."
Special moment
Liverpool parted ways with Arne Slot and appointed former Bournemouth boss Iraola after a disappointing fifth-place finish in the Premier League last season.
The 44-year-old Spaniard will take charge of the team at Anfield in a competitive home match for the first time when they host Nottingham Forest on Saturday.
"It is definitely a special moment for me," Iraola said. "I already felt it in pre-season.
"When the competition starts for me, I will be thinking of the game and the things I need to think of. But it is going to be emotional and I think it has to be like this.
"It is a special place. I had to fight a lot to arrive to this place, and I hope everything goes well and I can enjoy the game."