FIFA has blocked Premier League clubs from selecting Brazilian players who they refused to release for international duty for five days at the request of the country’s Football Association.
The world governing body has applied Article 5 to enforce the restriction period of September 10-14, which would see players miss this weekend's round of Premier League fixtures and also Tuesday's Champions League matches.
The players who were not released for the World Cup qualifiers against Argentina and Peru are Raphinha of Leeds, Manchester United's Fred, Thiago Silva at Chelsea, Manchester City's Ederson and Gabriel Jesus, as well as Alisson, Roberto Firmino and Fabinho at Liverpool.
It would mean Fred and Thiago Silva would also be ineligible for Manchester United's visit to Young Boys and Chelsea's clash with Zenit St Petersburg in the Champions League on the Tuesday.
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The Football Association has also been contacted by FIFA regarding the matter. FIFA remain in talks with the FA and UK government to get the ban on quarantine exemptions lifted.
According to FIFA Article 22 of its Disciplinary Code, the sanctions that may be applied if these restrictions are ignored include fines and forfeiting the match 3-0, although it is unclear what might happen if Leeds and Liverpool, who meet at Elland Road on Super Sunday, both defied any FIFA ruling.
Last week, Sky Sports News reported that Chile, Mexico and Paraguay had called on FIFA to enforce the restriction period on Ben Brereton of Blackburn and Chile, Francisco Sierralta of Watford and Chile, Newcastle and Paraguay's Miguel Almiron and Raul Jimenez of Wolves and Mexico.
Premier League chief executive Richard Masters has e-mailed all 20 top-flight clubs telling them they are working on finding a solution to the issue.
It is understood negotiations between all parties are ongoing.
Premier League fixtures this weekend
Saturday September 11:
Crystal Palace vs Tottenham - kick-off 12.30pm
Arsenal vs Norwich - kick-off 3pm
Brentford vs Brighton - kick-off 3pm
Leicester vs Man City - kick-off 3pm
Man Utd vs Newcastle - kick-off 3pm
Southampton vs West Ham - kick-off 3pm
Watford vs Wolves - kick-off 3pm
Chelsea vs Aston Villa - kick-off 5.30pm, live on Sky Sports Premier League
Sunday September 12:
Leeds vs Liverpool - kick off 4.30pm, live on Sky Sports Premier League
Monday September 13:
Everton vs Burnley - kick-off 8pm, live on Sky Sports Premier League