Indian budget airline IndiGo has signed a preliminary order with Airbus for 250 A320neo Family aircraft.
Airbus said on Wednesday that the memorandum of understanding with IndiGo, India's largest domestic airline, will become Airbus' single largest order - ever - by number of aircraft.
Aditya Ghosh, President of IndiGo said that this reaffirms their commitment to "the long-term development of affordable air transportation in India and overseas."
The A320neo had its first flight only last month in France.
Airbus President and CEO Fabrice Bregier said it builds on "the outstanding success of the A320 Family."
The A320neo "new engine option," Airbus says, will reduce the amount of CO2 per aircraft per year to 5,000 tons.
IndiGo has the right to pull the plug on the order at any time.