La Liga president Javier Tebas has revealed that Atletico Madrid have written to the league to request that Antoine Griezmann's registration with Barcelona is blocked.
Barca confirmed the signing of the France international last week, with the Spanish champions paying the attacker's £108m release clause.
Atletico, though, have claimed that a deal was agreed when Griezmann's buy-out figure was still at £180m and therefore the capital giants are requesting more money from the Spanish champions.
Tebas has said that the league have been contacted by Atletico and a review will be held.
"Atletico wrote to us and placed in doubt whether or not we should grant Griezmann's licence at Barcelona," Tebas told Onda Cero.
"There is a mechanism that has been put in place and it will be the organisations that must resolve the situation. We don't have the element of judgement."
Griezmann, who turned down a switch to Camp Nou last summer, made his debut for Barca against Chelsea in the International Champions Cup on Tuesday.
