A FIFA spokesperson confirmed proceedings had been opened against the Football Association of Ireland
Ireland's commemoration of the 100th anniversary of the country's Easter Uprising on their shirts has become more sensitive with England and Scotland locked in a battle with FIFA over the wearing of poppies in tribute to war dead.
A FIFA spokesperson confirmed proceedings had been opened against the FAI, adding: "We cannot comment further at this stage nor speculate on any outcome."
Meanwhile the FAI said Friday it had no comment to make on the situation beyond FIFA's brief announcement.
The Easter Rising which took place in April 1916 was an Irish rebellion against British rule.
The Republic of Ireland had the years 1916-2016 on their jerseys for the March 25 friendly against Switzerland.
England and Scotland have used the Irish example in their negotiations with FIFA over whether they can wear poppies on black armbands when they play each other in a World Cup qualifier at Wembley on November 11, which is Armistice Day and the traditional day for Britons to pay tribute to their war dead.
FIFA has rejected the poppy saying it is a political symbol.
A compromise was reached with FIFA to allow England players to wear a poppy armband during the friendly against Spain in November 2011, but world football chiefs have so far taken a tougher stance in this instance.
In a statement issued Thursday, the global governing body said: "FIFA fully respects the significance of commemorating Remembrance Day on November 11 each year.
"The Laws of the Game are overseen by the International Football Association Board (composed of the four British FAs and FIFA) and (are) applicable to all 211 member associations. The relevant Law 4, para. 4, clearly states that the players equipment should not carry any political, religious or commercial messages.
"The Laws are applied uniformly in the event of similar requests by any member association to commemorate similar historic events."