Etihad Airways confirmed that it had acquired a 2.987 per cent stake in Aer Lingus.
The airline said the purchase reflected its desire to forge a commercial partnership with the Irish national carrier.
Etihad Airways believes a possible partnership could produce significant commercial benefits for both airlines.
Etihad Airways operates 10 flights a week from Abu Dhabi to Dublin and has carried more than 750,000 passengers between the two capitals since it began flying the route in July, 2007.
The airline has a premium lounge at Dublin Airport, an engineering maintenance facility and has conducted recruitment drives across the country. It also recently renewed its sponsorship of the Gaelic Athletic Association, signing a five-year deal.