Although the inclusion of an unprecedented extra team would cause serious logistical problems including extra un-scheduled matches, Blatter said the FIFA executive committee would consider Ireland's request at their extra-ordinary meeting on Wednesday.
Ireland were eliminated from the competition earlier this month by France after Thierry Henry handled the ball in the build-up to William Gallas's equaliser that gave France a 1-1 draw and a 2-1 aggregate play-off win.
"We received a delegation from Ireland at FIFA and they were naturally absolutely unhappy at what has happened. They know the match cannot be replayed and the decision of the referee is final," Blatter told a keynote address at the Soccerex business conference.
"Naturally they have not asked for any sanctions to be given to any player or the referee, but they have asked, very humbly 'can't we be team No.33 at the World Cup? They have asked for that, really.
"I will bring it to the attention of the Executive Committee. I cannot confirm what will happen, but I will report it to the executive committee."
In a statement the FAI confirmed that it made the request to Blatter when a delegation met him in Zurich last Friday.
"A lot was discussed at the meeting and at one stage the FAI asked if Ireland could be accommodated into the World Cup 2010," said the statement.
However Irish sources have privately acknowledged they are not expecting their request to be successful, but have asked FIFA to consider compensating them in some other way in future, perhaps by being seeded in the draw for the 2014 finals.
The statement continued: "Other suggestions were also made to mitigate against further occurrences of such incidents, including the use of additional goal line assistant referees for FIFA international matches, further use of video technology for matches at the highest level, stronger provisions to discourage players from engaging in such blatant breaches of the Laws of the Game and provisions to strengthen referee selection for such important matches."
The draw for what is still likely to be a 32-team World Cup will take place in Cape Town on Friday.
