London - FIFA has opened disciplinary proceedings against Wales and Northern Ireland over the display of commemorative poppy symbols in their recent matches, the world governing body announced on Wednesday.
Both countries' football associations opted against allowing their players to wear black armbands with poppy symbols, but they have been charged anyway. Both have vowed to contest the charges.
FIFA previously announced disciplinary proceedings against England and Scotland, whose players wore poppy armbands during their Armistice day World Cup qualifier at Wembley.
"The disciplinary committee decided to open proceedings against the Irish Football Association and the Football Association of Wales in relation to several incidents involving the display of signs reported after the matches Northern Ireland-Azerbaijan and Wales-Serbia respectively," a FIFA spokesperson said.
People in Britain traditionally wear paper poppies or brooches in the days leading up to November 11, the day the Armistice was signed at the end of World War I in 1918, to remember the country's war dead.
Teams in the English Premier League wear poppy symbols on their shirts.
But FIFA's rule 4.4 forbids international teams from displaying political, religious or commercial symbols.
Wales laid a wreath beside the pitch and fans held up a poppy mosaic prior to their 1-1 World Cup qualifying draw in Cardiff earlier this month.
In Belfast, Northern Ireland held a minute's silence, laid wreaths and displayed a poppy mosaic ahead of their 4-0 win over Azerbaijan.
Football Association of Wales chief executive John Ford said he was "disappointed and surprised" by the news.
"Our intention was to show respect on Armistice weekend, which we feel we did in the right and proper way," he said in a statement.
"We also adhered to the rules and regulations of the competition and the communication from FIFA prohibiting the FAW request for the players to wear the poppy symbol on the armbands or the field of play.
"We are particularly disappointed that one of the charges relates to supporters in the stands wearing poppies. Naturally as an association we will strongly contest the charges."
The FAW expressed shock that among the incidents FIFA is investigating is the fact "some supporters in the stands (were) wearing the poppy".
The Irish Football Association said it would "robustly defend" itself against the charges.
Wales, Northern Ireland, England and Scotland could be docked World Cup qualifying points, but fines are thought more likely.