Barcelona coach Ronald Koeman has said it is frustrating the club are unable to compete with Manchester United, Manchester City and Paris Saint-Germain in the transfer market.

PSG signed Lionel Messi from Barca on a free transfer earlier this summer because the Catalan club could not afford to register his contract with LaLiga. The French side have also brought in Gianluigi Donnarumma, Sergio Ramos, Achraf Hakimi and Georginio Wijnaldum.

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City, meanwhile, spent £100 million on Jack Grealish, while Manchester United are set to follow up the signings of Jadon Sancho and Raphael Varane by bringing Cristiano Ronaldo back to the club from Juventus.

Barca have replaced Messi with Memphis Depay and Sergio Aguero, both players arriving on free transfers, but financial limitations have prevented them from spending any money, despite Koeman's desire to strengthen the squad. Barcelona president Joan Laporta has revealed that the club's debt now totals €1.35 billion.

"On the one hand I understand it," Koeman said in a news conference on Saturday when asked if he sympathised with the supporters' frustrations.

"For everyone that wants the best for the club, it's frustrating, I understand it. On the other hand, we have to be realistic. Economically, the club can't compete with other clubs, with Paris, City, United. That's how it is at the moment.

"We can't demand what has been demanded before at this club. We have to understand the moment the club is in."

Koeman had hoped Barca would be able to move on some of their bigger earners to make room for another addition in attack before the transfer window closes on Tuesday.

However, the Dutch coach has been angered by certain players' decisions to stay at put at Camp Nou, leaving him with a far bigger squad than he would like.

"The club know what I want and who I want to keep working with," he added. "I have always said I respect the players with contracts, but everyone knows perfectly well who we count on in this squad and who will have a hard time playing games.

"For some players, it's very complicated and it's not good for them or for us. If we have all our players back, we are going to have 31, 32 players. It's impossible to work with that many. How can a coach manage 32 players?"

Samuel Umtiti is one of the players set to stay at Barca despite the club trying to move him on, but Koeman confirmed Miralem Pjanic and Ilaix Moriba could both leave before Tuesday's deadline.

Meanwhile, Marc-Andre ter Stegen, Oscar Mingueza and Philippe Coutinho have all returned to the squad for Sunday's LaLiga game against Getafe at Camp Nou.

However, Barca are without the suspended Eric Garcia, while Gerard Pique, Ousmane Dembele, Ansu Fati and Sergio Aguero are all injured. Pedri has been given a rest.