Aer Lingus has officially agreed to become part of IAG after 95.77 per cent of its shareholders backed the takeover.
IAG confirmed its €1.3bn (£940 million) offer was earlier formally accepted by Ryanair, which had owned 29.8 per cent of the rival Irish airline.
This allowed Aer Lingus shareholders to move forward with their vote yesterday.
The remaining shareholders have until September 1 to accept IAG’s takeover, which is now unconditional.
IAG chief executive Willie Walsh said: “We’d like to welcome Aer Lingus into IAG. It will remain an iconic Irish brand with its base and management team in Ireland but will now grow as part of a strong, profitable airline group.
“This means new routes and more jobs benefitting customers, employees and the Irish economy and tourism.”
IAG also owns British Airways, Iberia and Vueling.
Last month, the European Commission approved IAG’s Aer Lingus takeover (see news, July 15).