DUBLIN (Reuters) - Ryanair (>> Ryanair Holdings plc) on Tuesday formally agreed to sell its stake in Aer Lingus (>> Aer Lingus Group Plc) to British Airways owner International Airlines Group (>> International Consolidated Airlns Grp SA), giving IAG the approval of over 90 percent of shareholders in Ireland's former flag carrier.

"We submitted our acceptance of the IAG offer today (18 Aug)," a Ryanair spokesman said in an emailed statement when asked if it had agreed to sell its 30 percent stake.

Ryanair's board of directors approved the sale in early July, but it failed to formally accept the offer before a July 30 deadline, which IAG then extended to Aug. 18. 

(Reporting by Conor Humphries; editing by Susan Thomas)