Sean Doyle, Aer Lingus Chairman and Chief Executive, is taking up the CEO role at British Airways.
Mr Doyle’s appointment comes as part of a number of changes to senior management at IAG.
The Cork native will also become chairman of the airline after a transition period.
IAG Chief Executive, Luis Gallego, said: “IAG has proved itself to be one of the world’s leading airline groups with a portfolio of successful companies.
“We’re navigating the worst crisis faced in our industry and I’m confident these internal promotions will ensure IAG is well placed to emerge in a strong position.”