England and Scotland football players wore black armbands bearing a red poppy during the World Cup qualifying match at Wembley, despite having their request to to wear the symbol turned down by Fifa.
The world football's governing body had refused to give the teams clearance to wear the poppy to mark Armistice Day, citing their rules regarding political and religious statements.
England and Scotland could now face a points deduction, a fine, or both.
While Fifa denied imposing a ban on wearing the commemorative emblem, it had reminded all four of the Home Nation associations of the rules - which when ignored can be passed onto Fifa’s disciplinary committee.
Northern Ireland's players wore plain black armbands for their World Cup qualifier against Azerbaijan in Belfast on Friday, and Wales will wear plain black armbands when they face Serbia on Saturday.
Fifa’s governing body has warned that they see the poppy as a political symbol, with general secretary Fatima Samba Diouf Samoura saying “any kind of sanction” could be handed to teams that rebel against the regulations – including a points deduction.
England won Friday's qualifying match 3-0, with goals from Daniel Sturridge, Adam Lallana and Gary Cahill.
Join our new commenting forum
Join thought-provoking conversations, follow other Independent readers and see their replies