Neymar's Paris St-Germain debut could be delayed again as French football authorities have still not received clearance following his world record 222m euro (£200m) move from Barcelona.
The Spanish football federation has until Thursday night to send the necessary documents, according to the LFP which runs France's Ligue 1.
If the deadline is missed, Neymar won't play for PSG at Guingamp on Sunday.
LFP has told BBC Sport "an official procedure" is being launched with Fifa.
But Fifa says it has not been contacted by French authorities about Neymar.
The Spanish football federation is yet to comment.
Brazilian Neymar, 25, has already had to miss Saturday's Ligue 1 win over Amiens.
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How do international transfers work?
Transfers between clubs in different countries must include Fifa's International Transfer Certificate (CIT). It is this document that the French football authorities are yet to receive.
"The Spanish federation of football has until Thursday night to send the CIT to the French federation of football, who send it back to the French professional football league, and then Neymar can play with PSG this weekend", an LFP statement said.
Neymar's move to France has been troubled since the release clause in his contract was triggered.
Spain's La Liga believes PSG are violating Uefa's Financial Fair Play (FFP) rules and Barcelona previously said they would report the French club to European football's governing body, Uefa, for a FFP breach.
PSG believes La Liga is acting unlawfully, while the LFP said it was "surprised" and urged the Spanish federation to "abide by the Fifa rules".
Fifa's step-by-step system explained:
- The new club approach the selling club with the transfer offer and details of the player they want to buy/loan.
- Once the terms are agreed, the football association representing the selling club must then confirm the player's identity in Fifa transfer system (ITMS).
- Fifa then confirm the process can continue.
- The football association of the new club request an International Transfer Certificate from the association of the selling club.
- The selling club's association can then accept or refuse the request - with an explanation.
- If the certificate is delivered, the player's registration date must be added to the Fifa transfer system.
- The player now becomes eligible to play for his new club.
- The payments are transferred between the clubs and receipts are added to the Fifa documents.
- The transfer is complete.