Atletico Madrid are disputing Barcelona's deal to sign Antoine Griezmann, stating that the fee paid falls £72m short of his release clause.
Barcelona released a statement on Friday afternoon claiming they had signed the 28-year-old after meeting the £108m buyout clause needed to terminate his contract with Atletico Madrid.
However, Atletico responded stating that the money paid was not enough, claiming that Griezmann had agreed to move to the Nou Camp before July 1, when his £180m release clause was slashed down to £108m.
"Atlético de Madrid believes that the amount deposited is insufficient to meet [Griezmann's] buy-out clause, since it is obvious that the player committed to FC Barcelona before the aforementioned clause was reduced from 200 to 120 million euros," the club said in a statement.
"Atlético de Madrid believes that the termination of the contract occurred before the end of last season due to events, acts and demonstrations carried out by the player and that is why the club has already started the procedures it considers appropriate for the defense of its legitimate rights and interests."
The French World Cup winner will be presented as a Barcelona player in the coming days and will sign a five-year deal, with his new contract carrying an €800m (£717m) buyout clause.
Sky Sports News reported on Thursday that Barcelona were set to pay Griezmann's £108m buyout clause, which the Spanish champions have now done.
Griezmann decided last summer to prolong his stay at Atletico, revealing his decision to snub Barca's offer in a documentary - which stoked tensions between the player and the club - not least because it was made by the production company owned by Barca defender Gerard Pique.
The 28-year-old signed a new deal with Atletico until 2023 containing a buy-out clause of €200m (£179m), which dropped to £108m on July 1 2019.
The former Real Sociedad forward departs Atletico after five prolific seasons in the capital, which saw him score 133 goals as well as help the club win the Europa League, UEFA Super Cup and Spanish Supercopa.
Griezmann's new task will be to help Barcelona win the Champions League for a sixth time.
Their last European title was in 2015, and the team collapsed in the second leg of last year's semi-final when Liverpool overturned a 3-0 loss by dealing them a humiliating 4-0 defeat.
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