O'Neill met the media in Dublin's Gibson Hotel for the first time since his appointment was revealed earlier this week - he has signed a two-year contract to replace Giovanni Trapattoni.
He took the press conference on his own, though, and confirmed during a lengthy questioning session that Keane was away watching Aston Villa play Cardiff.
Their first game in charge will be on Friday when Latvia are the visitors to the Aviva Stadium, and they travel to face Poland four days later.
O'Neill said: "It is a genuine privilege and pleasure to be here today. When I thought about it, I thought this opportunity might not be afforded to me again.
"I never lost the energy or enthusiasm. I was very disappointed (to be sacked by Sunderland). It's gone. I never lost the energy, it's what keeps me going.
"I wish there were some competitive games coming up quickly. My remit is to get the team to France (Euro 2016). That is my driving ambition.
"I'm hoping they (the fans) come back and the only way we can win them back is with a little style and a little panache,
"I would like to get these two games out of the way. If anyone is going to be of value to the setup I would be okay with that. We have some very talented young players. I am dependant on the big players being available for the big games."
O'Neill admitted one of his main areas of concern was the gap between games and the time he might have to think about important wins or defeats.
"That was the thing I was pondering over most," he added. "At least when you lose a club match you have the next week to get it right."