O'Neill has revealed he spoke to Villa manager Paul Lambert about the demands the position would make on Keane's time before sanctioning the move, which will see the former Manchester United captain combine the two jobs.
O'Neill told the Irish Independent: "My view is if it doesn't impinge on the job here with Ireland, then in actual fact it will end up being good for him.
"I know that if we couldn't have made it work, he wouldn't have taken the job in the first place.
"If his commitments to us - both on the commercial side and certainly from my viewpoint in terms of the time working with players - is not impinged at all, then I'm happy for it to go ahead, genuinely happy.
"Villa have agreed to give him all that time with us and therefore I don't really have a problem with it. I spoke with Paul to see how he felt it was going to work.
"He said that he gives the players, the senior players who are not involved at international level, a lot of time off anyway during that time [international breaks] and even if they did come back for a day or two, they could cope with that."