La Liga president Javier Tebas has warned Barcelona that they will not be able to register Lionel Messi next season if they do not reduce their salary bill.
Messi's deal expires in nine days, and he has yet to make a public decision on whether he will extend his 20-year relationship with Barca.
President Joan Laporta remains optimistic that Messi will sign on to the new rules at the Camp Nou, but Tebas said Barca must ensure they stay within the salary limits imposed by the league.
"Barcelona has exceeded its salary limit," Tebas said on Monday. "I hope they can keep Messi, but to do that, they have to cut somewhere else."
Before the COVID-19 pandemic, Barca had the biggest cap of €671 million in Spain's top flight in 2019-20.
However, La Liga's new limit for the 2020-21 season was €382.7m. The Catalan club were given some leeway in terms of reducing pay, but this meant they were unable to register the Memphis Depay despite having agreed a fee with Lyon last September.
La Liga could technically prevent them from registering a new Messi contract or signing a new one this summer if they do not comply with certain financial rules.
Messi's most recent four-year deal, signed in 2017, was worth more than €500m, which included his annual wages, fees and signing bonus.
Barca's salary bill has risen since the end of the season, with the signings of Eric Garcia, Sergio Aguero, Emerson Royal and Depay.
Meanwhile, they are struggling to move up some of the club's highest earners, including Samuel Umtiti and Philippe Coutinho.
Barcelona still hope to sell players like Umtiti and Coutinho. Martin Braithwaite, Junior., Neto, Miralem Pjanic and Matthias are other names who face an uncertain future at the club.
Tebas, however, said Messi's renewal would be possible if Barca, whose gross debt is around €1.2 billion, takes measures this summer.
"The gravity of the situation depends on the resources they are able to generate," the La Liga chief said. "Barca will have to restructure their debt. If they manage it, the situation will not be dire.
"But they've taken their wage bill to the limit. And when the football has coughed up — or, better say, has punctured a lung — they don't want to absorb that loss of income. They must remedy .
"[In La Liga] of the €700m loss, half of it is for Barcelona. There are other big clubs that have made a big effort to avoid it. Real Madrid have made a commendable effort to ensure that May their losses not be the same. As Barca, who take the trophy for defeat."
On Sunday, Barca members approved a €525m loan from Goldman Sachs to help the club go through a difficult period financially.
Laporta said the money would not be used on signings, but would be used to pay off outstanding debts such as player salaries, installments of transfer fees and owed money to the tax office.
The loan can be repaid in 15 years and has a 3% interest rate.
ESPN revealed in May that Barca had taken an advance on loan before members at the general assembly approved it, to ensure they could make salary payments before the end of the season.