Gabon players owed $1.35m, unpaid since 2016
Fifa has given Gabon's football federation until Monday to explain how it is addressing salary arrears totalling just over $1.35 million and which sometimes date back to 2016.
As many as 20 clubs in the country that hosted the 2017 Africa Cup of Nations owe money to 'an important number of players'.
"We ask you to urgently take the necessary measures to address the issue," Fifa Secretary General Fatma Samoura wrote to the local FA (Fegafoot) on 1 July.
The Senegalese gave the organisation just one week to answer.
Several of the salary arrears date back to the 2016-2017 and 2017-2018 seasons.
The Confederation of African Football (Caf) had previously issued a warning to Fegafoot in June 2018.
African football's ruling body stated that if the arrears were not settled by the end of that month, Gabon's clubs would be barred from continental competition.
Nonetheless, both Mangasport and Cercle Mberi Sportif took part in last season's African Champions League and Confederation Cup respectively - despite the outstanding arrears.
"Fegafoot has the responsibility of looking after the rights of players," said Samoura, who is in line to work closely with Caf from 1 August in an unprecedented move.
"The non-payment by the concerned clubs of their financial obligations … cannot remain without a quick resolution."
In a survey published by global players' union FIFPro in 2016, 96% of players in Gabon reported payment delays.
Earlier that year, the head of the local Gabonese players' union (ANFPG) said that several players threatening a strike had received anonymous threats.
Fifa has already stepped in to address belated payments in Gabon.
In December 2016, just a month before Gabon hosted the Nations Cup, football's world governing body helped ensure that Ivorian Mariano Beugre was paid outstanding wages from his period with Mangasport in 2014 and 2015.
The Moanda-based club is not believed to be among the 20 clubs that still owe salaries.
"Our football is deteriorating every day of every year simply because its leaders have not yet understood that the main player is the footballer," Remy Ebanega, president of the ANFPG, told BBC Sport back in 2017.
"Without a footballer, there is no club, no league, even less a federation."
Gabon, which failed to qualify for the ongoing Nations Cup in Egypt, is an oil-rich nation with one of Africa's highest GDPs per capita.