The two singers rose to fame while taking part in the x-factor in 2010.
Westmeath's Niall Horan has released a statement saying he's "absolutely devastated" at the death of his former band-mate.
Liam Payne, a former member of One Direction passed away suddenly after he fell from the balcony of a hotel in Argentina.
The singer was visiting the region to catch up with his old band mate at one of his shows.
The two singers rose to fame while taking part in the X-Factor in 2010.
In a social media post the Mullingar singer says, "I sadly didn't know that I would be saying goodbye forever."

Young people may take longer to fully process the death of Liam, and can feel grief in a more impactful way, according to a Westmeath psychotherapist.
It comes after the sudden death of the One Direction member on Wednesday night.
The former boyband singer died at the age of 31 after falling from his third floor hotel room balcony in Argentina.
His death has sent shockwaves around the world particularly with his younger fanbase.
Psychotherapist Siobhan Lijin from the Athlone Care Clinic says the teenage brain absorbs grief differently:
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