Atletico Madrid President, Enrique Cerezo, has warned Barcelona there will be consequences if they are found to have signed a pre-contract agreement with Antoine Griezmann while his release clause was higher than it is now.
Barcelona are expected to announce the Frenchman's signing next week with his release clause from Atletico having dropped from €200m (£180m) to €120m (£107m) on July 1.
Atletico Madrid Chief Executive Officer, Miguel Angel Gil, had said that he believed Griezmann agreed terms with Barcelona in March when his release clause was still at €200m (£180m).
However, Cerezo was asked on Thursday what would happen if it was proved Barcelona agreed terms with Griezmann in March.
He told Daily Mail: "The truth is I don't know, but if it is as you say and he had already signed, then there will be consequences.
"It does not seem normal to me but I do not know if he has signed or not or if he is going to Barcelona or not. I suppose in a few days we will find out."
Barcelona have appeared to go to great lengths to avoid being accused of illegally 'wooing' Griezmann since the middle of last season.
Players have said almost nothing about his imminent arrival and club officials have also been silent.