Cardiff City face a three-window transfer ban unless they pay French club Nantes the first installment for the transfer of Emiliano Sala who died in a plane crash on his way to join the Welsh club, world governing body FIFA said on Monday.

FIFA released the full reasoning for their September decision that Cardiff must pay the agreed first installment of 6 million euros (5.2 million pounds) to Nantes.

After signing for Cardiff for 15 million pounds in January, Sala was travelling to Wales from the French club when his plane crashed in the English Channel.

The body of the 28-year-old Argentine striker was recovered nearly three weeks later after an underwater search found the wreckage.

FIFA's Players' Status Committee said that if Cardiff does not pay the six million euros within 45 days of receiving bank details from Nantes, "A ban from registering any new players, either nationally or internationally, for the maximum duration of three entire and consecutive registration periods shall become effective".

The ban for three transfer windows would be lifted if Cardiff complied with the ruling in the meantime.

Cardiff City did not immediately respond to a request for comment but the club had previously stated they intend to take the matter to the Court of Arbitration for Sport in Switzerland.

"Cardiff City FC is extremely disappointed at the decision of the Players' Status Committee to award against the club," the Welsh club said after the initial verdict.

"It would appear the committee has reached its conclusion on a narrow aspect of the overall dispute, without considering the full documentation presented by Cardiff City FC to FIFA.

"Nevertheless, there remains clear evidence that the transfer agreement was never completed in accordance with multiple contractual requirements which were requested by Nantes, thereby rendering it null and void."

FIFA's ruling argued that the transfer had been officially completed before Sala's death and therefore Cardiff remained obliged to make agreed payments.

The club, relegated from the Premier League to the second-tier Championship last season, had argued that the circumstances surrounding Sala's death, in a plane organised by an agent who brokered the transfer, meant Nantes were liable for damages caused to them.