Fifa on Thursday refused to publicly rule out the prospect of a rematch in the wake of Thierry Henry's handball offence prior to France's decisive goal.
Henry admitted to handling the ball in the build-up to William Gallas's goal, which cancelled out Robbie Keane's strike and ensured World Cup qualification for the French in the Stade de France 2-1 on aggregate.
A day of anger in Ireland culminated with the Taoiseach [the head of the government of Ireland] Brian Cowen, backing Football Association of Ireland calls for a replay and confirming that he would "probably have a chat about it [with French President Nicolas Sarkozy] away from the table" at this week's European Union summit in Brussels.
The FAI on Thursday dispatched letters to Fifa and the FFF calling for the "integrity of the game" to be upheld by the staging of a replay.
With the FAI estimating that failure to qualify for South Africa will cost the organisation €15 million (£13.5 million), an appeal to the Court of Arbitration for Sport is also being considered should calls for a replay be rejected.
But despite issuing a statement earlier in the day pointing to law five of the Laws of the Game, which states that the decisions of the referee "regarding facts connected with play, including whether or not a goal is scored and the result of the match, are final", senior Fifa officials are understood to be reluctant to state their position publicly until the French have responded to the Irish.
The FAI has pointed to Fifa's decision to order a replay of the Asian Confederation World Cup play-off between Uzbekistan and Bahrain in 2005 due to a 'technical error' by the referee as a relevant precedent for the calls for a rematch.
The restaged FA Cup tie between Arsenal and Sheffield United in 1998, played following a controversial goal scored by Arsenal after United had kicked the ball out of play for the treatment of an injured player, has also been highlighted by the Irish.
And FAI chief executive John Delaney insists that both Fifa and the FFF have a duty to the game to ensure that the play-off fixture is replayed.
Delaney said: "It's up to the French federation. If they came out in the next 24 hours, I think Fifa would go with that.
"If there is goodwill, you can solve all these things. From a French federation point of view, they need to look at themselves. Thierry Henry is their captain and a wonderful footballer, but does he want to be remembered like Maradona where his legacy is a handball?
"I spoke with the French federation president and he said it was a handball. They have to step up to the plate.
"This is not just one football match. This is the whole world looking. There is a team that should be in the World Cup and that's us. We should be there.
"If I was the president of the French federation, I would want to go to South Africa deserving to be there. It was a travesty on Wednesday night, an injustice.
"Every time I got to a Fifa Congress, I hear about fair play and integrity. If Fifa really believe in fair play and integrity, this is their opportunity to step forward."
Ireland coach Giovanni Trapattoni has claimed it would be 'impossible' to have a replay and Fifa is known to be reluctant to impose such an eventuality.
However, with diplomatic pressure now being applied on the French by senior figures within the Irish government, Fifa is unlikely to block a rematch should the French agree to Irish demands.