I found this.
https://www.laliga.com/noticias/nota-informativa-contrato-lionel-messi
Translate:
In relation to the different interpretations (some of them contradictory among themselves) published in the last days in different media, related to the contractual situation of the player Lionel Andrés Messi with FC Barcelona, LaLiga considers it convenient to clarify that, once the contract of the player with his club has been analyzed:
The contract is currently in force and has a "termination clause" applicable in the event that Lionel Andrés Messi decides to urge the early unilateral termination of the contract, carried out in accordance with Article 16 of Royal Decree 1006/1985, of June 26, 1985, which regulates the special employment relationship of professional sportsmen.
In compliance with the applicable regulations, and following the procedure that corresponds in these cases, La Liga will not carry out the procedure of previous visa of federative discharge to the player if he has not paid previously the amount of this clause.