The SFA were today urged to act swiftly to help ex-Rangers players continue their careers away from Ibrox.
The SFA have been unable to process international clearance for stars such as Steven Naismith and Steven Davis, who exercised their right to leave the club when Sevco Scotland bought the assets of Rangers.
The matter is now in the hands of Fifa, who have written to Scotland's governing body seeking information.
One of the players, Kyle Lafferty, had been expected to make his competitive debut for Sion yesterday, but the Swiss club did not include him in the squad for their victory over Grasshoppers.
Margaret Gribbon, who legally represents seven of the players, has asked the SFA to move quickly to ensure they are able to launch their careers elsewhere.
She said: "Following the refusal of the SFA to issue players registrations, the new clubs have all referred the matter to Fifa.
"Fifa have now written to the SFA in each case requesting reasons why the players' registrations were blocked.
"It remains entirely unclear the facts and matters upon which Rangers oldco and Rangers newco rely in order to support their position that the players acted in breach of contract.
"Presumably they have made their reasons known to the SFA and if so, these have not been shared with my law firm, Bridge Litigation, who represent the majority of the players.
"Fifa have given the SFA seven days to respond but it is hoped that given the straightforward nature of the request the SFA will be in a position to reply sooner.
"We still remain confident that Fifa will grant ITC [International Transfer Clearance] enabling the players to continue playing football with their new clubs."
Sevco chief executive Charles Green has argued that the players were in breach of contract when they joined other clubs and chose not to stay on at a newco Rangers.
However, PFA Scotland believe that their members were free agents.