The amount of US$4 million was reportedly meant to be paid to 420 players by Sept. 30 of last year.
However, it has been reported that these payments destined for the out-of-pocket players have still not been made.
Emails and letters from global players' union FIFPro to FIFA chasing up the payment have reportedly gone unanswered.
Many of the players impacted are believed to be based in Portugal, Greece and Romania. Although the figure of 420 does also include players from all over the world.
The sum is part of the FIFA Fund for Football Players (FFP), which was set up in 2020 following an agreement between the governing body and FIFPro.
FIFA set aside $16 million at the fund's launch, with the aim of providing "financial support to players who have not been paid and have no chance of duly receiving the wages agreed with their clubs," as per Inside FIFA.
The reports follow the filing of a complaint last week by bodies representing footballers and clubs in Europe, including FIFPro, which accuses FIFA of abusing its position over changes to the international match calendar and tournament expansions.