Mohamed Salah is among four Liverpool players not being released for international dutyPremier League sides are among leading European clubs set to prevent players from going to red-list countries for September's international break.
Unless quarantine exemptions are made, players would be forced to miss several domestic league matches because of the 10-day isolation period required on return to the UK.
The Football Association and Premier League are in talks with the Department for Digital, Culture, Media and Sport (DCMS) over a relaxation of UK rules. Similar problems are thought to confront clubs across Europe.
Liverpool are among the clubs refusing to release players for international duty.
Four Reds players are affected - Egypt forward Mohamed Salah and Brazil trio Alisson, Fabinho and Roberto Firmino - because their home nations are on the UK government's red listexternal-link.
The Egyptian Football Association said on its website that Liverpool had apologised for not allowing Salah to join up with the national team.
Its statement read: "The Egyptian Football Association has received a letter from Liverpool apologising for the inability of its player, Mohamed Salah, to join the national team in its next camp, which includes facing Angola in Cairo and Gabon in Franceville during the first and second rounds of the African continent's qualifiers for the World Cup."
However, Liverpool have confirmed that they are happy for Salah to play in the away fixture against Gabon because of not having to enter a red-list country.
The key issue for Liverpool and other Premier League clubs is the absence of an exemption to the existing UK quarantine rules. Were there to be one, it is understood players would be released.
In an additional headache for some Premier League clubs, Fifa recently extended the September and October international windows by two days in South America to enable countries to catch up on World Cup qualifiers that were postponed because of the coronavirus pandemic.
The governing body also said the two-day extension ensured "sufficient rest and preparation time between matches".external-link
It means matches can now be played on Thursday, 9 September and Thursday, 14 October, with players involved being released for 11 days.
Among the games scheduled for Thursday 9 September are Argentina v Bolivia (Friday 00:30 BST) and Brazil v Peru (Friday 01:30 BST).
Because of the time difference, players involved in those games may not return to their clubs until Saturday, 11 September, when eight Premier League matches are scheduled to take place.
Brazil, whose latest squad includes nine Premier League players, are due to play Argentina, Chile and Peru in next month's qualifiers. All four countries are currently on the UK's red list.
With just under 100 English-based players likely to be unavailable for international matches next month, the Premier League, the FA, the European Club Association and its member clubs are all understood to want a solution as quickly as possible, with exemption from quarantine rules thought to be the starting point.
The government denied exemptions to British and Irish Lions players returning from South Africa earlier this month, but has confirmed that it continues to have regular discussions with the Premier League, FA and other sporting bodies about a variety of issues, including international travel rules.
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