FIFA has stated information regarding David de Gea's seemingly failed transfer from Manchester United to Real Madrid is "confidential" amid suggestions of an appeal.

The Spain goalkeeper looked set to complete his long-mooted switch to the Santiago Bernabeu on Monday, but De Gea was left in limbo after the deadline passed in his home country without a move being finalised.

Reports in Spain have suggested a missed deadline in filing the relevant paperwork scuppered the deal.

There have been suggestions the clubs could appeal to FIFA over the delay, but world football's governing body kept tight-lipped over whether information regarding the deal had been entered into its International Transfer Matching System (ITMS) in time.

"In terms of TMS processing paperwork etc. the information in the International Transfer Matching System is confidential to the registered users of ITMS," said a FIFA spokesperson.

"We are therefore not in a position to give information on transfers."

As it stands, De Gea looks set to remain at Old Trafford until at least January.

The 24-year-old has lost his place as United's number one to Sergio Romero after Louis van Gaal stated De Gea was not in the right frame of mind to play against the backdrop his his protracted transfer saga.