Through the origins of his grandparents, Keary is eligible to represent the northern hemisphere nation, a move he had previously hoped to occur at the 2017 World Cup in Australia.
A hip injury hampered Keary's hopes of representing Ireland five years ago, with his dream a chance to be rekindled this year ahead of the October-November tournament.
“I stuck my hand up to play for Ireland in 2017,” Keary told The Sydney Morning Herald.
“It didn’t eventuate, I had a few [injuries] at the back end of the year. We’ll just see how the next few weeks go but I’ve told the [Irish officials] that I need to tell.
“I’ve always had a connection there since I was a kid. Dad’s family is still over there. I haven’t been over there but you just feel proud whenever he talked about it. It makes me feel good thinking about it.
“It’s going to be a great World Cup with so many great players putting their hands up for their nations of birth or their heritage. I think it’s great for our game.”
Ireland will begin their World Cup campaign against Jamaica at Headingley on October 16, with the tier-two nation facing further tests against Lebanon and New Zealand in the group stages.