DUBAI, United Arab Emirates (AP) — Qatar Airways said Wednesday it has increased its share in the parent company of British Airways, International Airlines Group, from 21.4 % to 25.1%.

IAG, which operates a number of other European carriers such as Ireland’s Aer Lingus and Spain’s Iberia, is one of the world’s largest airline groups, with 573 aircraft carrying around 118 million passengers a year. It is a Spanish registered company with shares traded on the London and Spanish stock exchanges.

Qatar Airways Group Chief Executive Akbar Al Baker said the decision to increase the company’s stake in IAG is a reflection of how successful its investment in the European airline group has been to date.

Qatar’s Doha-based national carrier is among the biggest and fastest-growing airlines in the Middle East, but its growth has been hampered over the past two years by flight restrictions from three neighboring Gulf states and Egypt, which are locked in a political dispute with Qatar.