Frontier Airlines has unveiled plans to add new domestic and international routes from Ontario International Airport in California, the US.

The Denver-based airline will add new direct routes to Newark in New York, Miami in Florida and Las Vegas in California.

Plans to launch international services to El Salvador and Guatemala are also underway.

Daily services to Newark Liberty International Airport, Miami International Airport and Las Vegas’ McCarran International Airport will commence from 23 April.

Flights to El Salvador International Airport Saint Oscar Arnulfo Romero y Galdámez will operate four times a week from 7 May.

The service to La Aurora International Airport in Guatemala City will be offered three times a week from 18 June.

Capable of accommodating 180 passengers, the Airbus A320 will serve these new routes.

With the introduction of the new services, the airline’s passengers at Ontario Airport can now travel to more than 12 destinations.

Frontier Airlines also operates flights to Denver in Colorado, Austin in Texas and Orlando in Florida from the airport’s second terminal.

Ontario International Airport Authority (OIAA) Board of Commissioners president Alan D Wapner said: “This significant expansion of air service adds to Ontario’s momentum and reaffirms our status as the nation’s fasting growing airport.

“At a time when few airports in Southern California are consistently attracting more air travellers, Ontario is bucking the trend with double-digit passenger growth, which is good news for the Inland Empire economy.”

This year, Ontario International Airport recorded an 11.6% passenger volume increase in the month of September.

OIAA revealed that the month’s domestic passenger volume reached 446,169, an increase of 10.8% from September last year. International travellers increased by 29.8% to 23,155.