US-based airline Allegiant has entered into an agreement to buy four more Airbus A319 aircraft from Philippines-based low-cost carrier Cebu Pacific.

The deal is in line with the company’s long-term transition to an all Airbus fleet.

Allegiant previously agreed to buy six Airbus A319 from Cebu Pacific and the newly ordered aircraft are to be delivered between next year and 2018.

"This agreement to purchase additional aircraft from Cebu Pacific is an important step in our long-term transition to a single fleet type."

The company has already received three of the previously ordered aircraft, with the remaining deliveries scheduled later this year.

By the end of this year, Allegiant’s in-service Airbus fleet will include 16 A320s and 17 A319s, and have a total of 85 aircraft in revenue service.

Allegiant Travel Company chief operating officer Jude Bricker said: "By the end of 2016, Allegiant will be a majority Airbus carrier, as measured by available seat miles.

"This agreement to purchase additional aircraft from Cebu Pacific is an important step in our long-term transition to a single fleet type."

With a fleet of A320 family aircraft, Allegiant aims to increase its operational efficiency and open up new growth opportunities by making longer routes and off-peak flying.

The company’s new business model has also enabled it to provide access to low-cost flights in more than 100 cities across the US.