MANILA - The Ninoy Aquino International Airport (NAIA) Terminals 2 and 3 need to be "rationalized" and not be used for both domestic and international flights, a key airport official said on Thursday.

Manila International Airport Authority (MIAA) General Manager Ed Monreal said NAIA Terminal 2, which is currently being used by Philippine Airlines (PAL), was originally designed as a domestic terminal, while NAIA Terminal 3, which is being used by several airlines, was designed for international flights.

Using the two terminals for both domestic and international flights has resulted in congestion and inconvenience for passengers, Monreal told DZMM radio.

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"Sa aking palagay, ang the best way is to rationalize in a way na kailangan po ang paliparan ng Terminal 3 ay fully utilized as international, [at] ang domestic na Terminal 2 ay magamit na fully domestic," Monreal said.

(I think the best way is to rationalize the airport and fully utilize Terminal 3 for international flights, and Terminal 2 for domestic flights.)

He added that as early as June 2017, airport authorities had already drafted a plan for the rationalization of the airport, but airlines had reservations about this citing possible disruption in their operations.

House Speaker Pantaleon Alvarez said Thursday carriers have 45 days to help decongest NAIA by moving flights to Clark, or risk losing their franchise.

Alvarez singled out Cebu Pacific, the country's largest carrier, calling it "hard-headed," unlike its rival, PAL.

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Monreal said airport authorities are ready to work within the 45-day deadline set by Alvarez.