International Airlines Group (IAG) chief Willie Walsh announced on early Thursday that he was stepping down, and is set to retire on 30 June.
Mr Walsh, 58, stated that it was a "privilege" to help merge British Airways with Spanish carrier Iberia, leading to IAG's creation. IAG chairman Antonio Vázquez, called the former CEO one of the main drivers of the merger.
"It has been a privilege to have been instrumental in the creation and development of IAG. I have had the pleasure of working with many exceptional people over the past 15 years at British Airways and at IAG," Mr Walsh said in a press release.
IAG Group also controls Spain's Vueling and Irish carrier Aer Lingus, with Mr Walsh joining the latter in the late 1970s as a cadet pilot. He later was appointed CEO of Aer Lingus in 2001 after building his career.
IAG head in Spain, Mr Luis Gallego, will take over duties for Mr Walsh.
"It is a huge honour to lead this great company. It is an exciting time at IAG and I am confident that we can build on the strong foundations created by Willie," Mr Gallego said.
The news comes after British Airways saw massive disruptions and flight cancellations due to system IT failures and pilot strikes, among others. In November, numerous BA flights were delayed and cancelled due to the problems and later incurred a £138m fine in July due to a data breach which exposed customer information. The events pushed down BA's customer satisfaction rating to 55 percent for its short and long-haul flights, according to consumer survey group Which, ranking the flagship carrier below low-cost airlines such as easyJet and others.