European aviation giant Airbus announced Thursday that Saudi low-cost carrier flynas has signed a deal to buy 75 single-aisle A320neo jets and 15 long-haul A330-900 planes.

The planes have a catalogue price totalling $13 billion, though big orders usually have significant discounts.

The two sides signed a memorandum of understanding at the UK's Farnborough International Airshow, an event that also landed large orders for Airbus's US rival Boeing this week.

An MoU means that the two companies agree on a purchase in principle, with details to be worked out later, as opposed to a firm order that would include payments.

Flynas, which was founded in 2007, only uses Airbus planes. Its fleet includes 52 A320 planes and four A330 jets that it rents.

The company has already ordered 65 A320 and A321 planes.

The A330 ordered by flynas will be modified to fit 400 passengers, Airbus said, instead of up to 300 under the current configuration.

"The A330neo will enhance our long-haul capabilities with its advanced technology and efficiency while supporting our growth plans and Saudi Arabia's (Mecca) pilgrim program," said flynas chief executive Bander Almohanna.