The Bluebirds claim they are looking into all the details of the deal to sign the striker, which is why they have yet to pay the Ligue 1 side
Cardiff City chairman Mehmet Dalman has confirmed Nantes have threatened legal action over the Bluebirds not yet having paid a transfer fee for Emiliano Sala.
Sala was heading to Cardiff after completing a club-record move from the Ligue 1 side when the Piper Malibu aircraft carrying both the player and pilot David Ibbotson disappeared on January 21.
The 28-year-old's body was recovered with the help of specialist contractors from the plane wreckage in the English Channel last week.