Liverpool defender Joel Matip could face a three-week suspension over his decision to turn down a call-up from Cameroon for the Africa Cup of Nations.
Matip is one of seven Cameroon players to have ruled themselves out of the tournament, including West Bromwich Albion full-back Allan Nyom.
However, the Cameroon football association (Fecafoot) has suggested that it could look to take action against the players, with their options including asking FIFA to suspend them from club duty for the duration of the three-week tournament.
"These players have put personal interest above those of the national team and the federation reserves the right to take action against the players in accordance with FIFA regulations," Cameroon coach Hugo Broos said in a statement.
Andre Onana (Ajax), Guy N'dy Assembe (Nancy), Maxime Poundje (Bordeaux), Andre-Frank Zambo Anguissa (Marseille) and Ibrahim Amadou (Lille) have also ruled themselves out despite being included in the preliminary 35-man squad.
Cameroon have been drawn in Group A of the tournament alongside hosts Gabon, Burkina Faso and Guinea Bissau.
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