FIFA have said that retrospective action is unlikely following the disclosure that three Ireland players - Tony Cascarino, John Aldridge and Jason McAteer - have been in breach of the association's eligibility rules.

All three have only recently come into possession of Irish passports, even though their credentials for holding them were established a long time ago.

FIFA rules demand that players hold a passport issued by the country they represent. But, strangely, the rule has never been rigidly enforced until this year.

In the past, passports were examined only on occasions of major championship finals, but now observers are instructed to check them at every game.

Bernard O'Byrne, the FAI chief executive, said there was no question of the association having ever fielded an "illegal" player, but he conceded that the three players did not hold a passport at the time of the earlier World Cup games this season.

"Although the rules state that players must be in possession of valid passports to play in international football, it is one which was never strictly enforced until now.

"The important factor is and always has been that players are eligible to hold passports for the country they represent, and in our case there was never any question about this," O'Byrne said.

"Because of the emergence of new countries in eastern Europe, greater emphasis is now being placed on the production of passports for identification purposes and we have acted accordingly."

The problem first came to light from an Irish viewpoint when the official FIFA observer at the game in Liechtenstein in August pointed out that Cascarino was carrying a British passport.

Aldridge and McAteer were later queried on similar grounds by the observer at last month's game against Macedonia and, in the light of those comments, the FAI decided to act.

Cascarino was furnished with the requisite Irish documents last month, and this week both Aldridge and McAteer successfully applied in the courts for Irish nationality.