DUBAI: Airbus is close to agreeing a blockbuster order worth more than $40 billion at list prices to sell around 400 aircraft to U.S.-based investment fund Indigo Partners, founded by low-cost airline pioneer Bill Franke, two sources said.

The sources, who were familiar with the matter, said the deal could be unveiled at the Dubai Airshow later on Wednesday in a huge comeback for the European planemaker, which had so far been upstaged by rival Boeing Co at the airshow and in the annual aircraft orders race.

Airbus and Indigo Partners declined to comment.

(Reporting by Tim Hepher in Dubai; Editing by Himani Sarkar) ((Jamie.Freed@thomsonreuters.com; +65 6318 4789;))