Investigators will begin interviewing the heads of the 25 Caribbean associations at the centre of the FIFA bribery scandal today.
FIFA's ethics committee have summoned all 25 associations to the interviews in Miami to be questioned about claims they were each offered or given 40,000 US dollars as a bribe by senior FIFA members Mohamed Bin Hammam and Jack Warner.
A letter from FIFA to the associations has been obtained by Sky News, telling federation chiefs to meet investigators from June 7-9. The interviews are being carried out by officials from Freeh Group International Europe - the agency run by ex-FBI director Louis Freeh - which has been hired by FIFA to assist Robert Torres, the ethics committee member leading the probe.
The letter states: "Although you are under no obligation to attend such a meeting please be advised that the FIFA ethics committee may draw a negative inference in the event that you (i) do not make the arrangements sought herein, or (ii) do not attend the meeting requested.
"Furthermore we kindly remind you that as an official you have a duty of disclosure and reporting, including providing any evidence requested for inspection."
FIFA say they will pick up the tab for travel to and accommodation in Miami and say if officials cannot make the dates requested they must offer an alternative to take place within the next 10 days.
Bin Hammam and Warner have been suspended pending the outcome of the probe, which is likely to be completed in mid-July. The bribes are alleged to have been paid to members of the Caribbean Football Union at a meeting in Trinidad on May 10 and 11.
One Caribbean association has complained to FIFA that the investigation is "biased" towards the USA - one of the defeated bids for the 2022 World Cup.
The letter of complaint, which has been seen by Press Association Sport, says: "The investigation is tainted and biased and clearly has a US-driven agenda."
It asks FIFA president Sepp Blatter to replace Freeh with a "truly independent investigator and secure a neutral venue for the interview of any Caribbean Football Union member other than the USA".
It also points out that former USA president Bill Clinton worked on the USA 2022 bid, during the time Freeh was FBI director, and that the main complainant, FIFA member Chuck Blazer is American, as are the investigators with the "interrogation being conducted on American soil".