His departure follows a row with manager Mick McCarthy over the team's training facilities and programme.
Steve Staunton will now take over as captain of the Ireland side for the tournament.
Last international match
And Keane has probably played his last international match as he earlier revealed his intention to concentrate on club duties following the World Cup.
McCarthy and the Football Association of Ireland are to seek special permission from Fifa to bring in Colin Healy to replace Keane.
But it's unlikely that will be granted, as the official deadline for squads to be named has now passed.
The news ends a three-day saga, in which Keane threatened to quit but was then persuaded to change his mind.
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