Flights are expected to be back to normal on Monday in Manila's main airport, after a power outage hit air navigation facilities and brought services to a halt on Sunday.

Ninoy Aquino International Airport officials say they have resumed normal operations.

The officials say at least 280 flights were delayed, cancelled or diverted to regional airports. About 56,000 passengers were affected.

The disruptions came as a power outage cut communications between airlines and the air traffic management center.

Flights between Manila and Japan's Narita and Haneda airports were canceled or returned. Those flights passing over or near the Philippines on their way to or from Southeast Asian countries were also disrupted.