Aer Lingus Group will become part of International Airlines Group after its offer for all outstanding shares was formally accepted.

Ryanair was the last piece to fall into place for, IAG with the Irish low-cost airline waiting until deadline day to accept the offer.

Ryanair’s acceptance was a condition of the offer which is now wholly unconditional as all the conditions have been satisfied.

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.”

The IAG offer for Aer Lingus will remain open for acceptance until the final closing date of 15:00 September 1st, 2015.

Aer Lingus shareholders who have not yet accepted the offer are encouraged to do so without delay, IAG said in a statement.