London - Qatar Airways has bought a 9.99% stake in International Airlines Group, worth around £1.15bn, building closer ties with the owner of its partners British Airways and Spain's Iberia in the oneworld alliance.
Qatar's national airline said it would look to strengthen commercial ties with the European company, and may consider increasing its stake over time, although it was not currently intending to exceed 9.99%.
"IAG represents an excellent opportunity to further develop our Westwards strategy," said Qatar Airways chief executive Akbar Al Baker said on Friday.
Non-European shareholders of IAG including Qatar Airways are subject to an overall cap on ownership, as a result of the requirement for EU airlines to be majority owned by EU shareholders.
IAG chief executive Willie Walsh welcomed the move. "We will talk to them about what opportunities exist to work more closely together and further IAG's ambitions," he said in a statement.
Qatar Airways, fully owned by the country's sovereign wealth fund, has competed with regional rivals Emirates and Etihad Airways to become major global carriers.
It joined oneworld in 2013, becoming the first Gulf airline in enter into a global alliance, which allows airlines to team up via code-sharing agreements to boost the number of flights they offer.