Soccer club Cardiff has formally filed an appeal to sport's highest court seeking to overturn a FIFA order it must pay Nantes a 6 million euros ($6.7 million) first payment for Emiliano Sala.

An appeal hearing is likely to be held around April, and a verdict “ is not expected before June," the Court of Arbitration for Sport said on Thursday.

FIFA ruled in favor of Nantes and warned Cardiff it faces a transfer ban of three trading windows if it refuses to pay when the case is settled.

Cardiff agreed in January to pay a club record fee for Argentine forward Sala, who died in a plane crash before playing for his new team.

Sala was killed when the single-engine aircraft carrying him from Nantes to Cardiff crashed near the Channel Island of Guernsey on Jan. 21.

Hours earlier, FIFA received an online document from the Welsh soccer federation to complete transferring the player's registration from France.