Earlier this month, the airline used to own a 15.67% shareholding in the group but has now upped the ownership to 20.01%, still within EU limits which states EU airlines must be majority owned by EU shareholders.

While Qatar Airways group chief executive Akbar Al Baker said the airline’s interest in the group was purely financial, the increased shareholding “reflects the strength of commercial and strategic ties between the companies and evidences the continued support for the ongoing strategy of IAG”.

He added: “The recent market valuation of one of the world’s leading airline groups has provided what we believe is an attractive opportunity to increase our shareholding in IAG.

“We continue to be highly supportive of IAG’s strategy and management team and we do not intend to increase our percentage shareholding further unless there are material changes to the current situation.”