Washington, Nov 14 (IANS) US aviation authorities began easing flight restrictions as technical and communications systems came back online after a nationwide ground stop, although officials said delays were expected to continue.

The Federal Aviation Administration had earlier ordered departing traffic held at airports across the country after a communications failure.

American Airlines said the ground stop remained in place, although some flights at certain airports were beginning to receive clearance to depart. Most departures remained paused, the airline said, warning of continued disruption and unavoidable cancellations.

Aviation journalist Jon Ostrower reported that multiple airline sources expected the nationwide ground stop to be lifted imminently.

Air India warned of possible disruption to flights to and from the United States and advised passengers to check their flight status before travelling to the airport.

"Passengers are advised to check the latest status of their flights and plan their journey to the airport accordingly," the airline said in a travel advisory.

In an operations plan, the FAA's Air Traffic Control System Command Centre said restrictions remained in effect across a large part of the country, although some coastal facilities had been able to release international departures.

The plan listed the restrictions through 11 p.m. Eastern.

The partial resumption followed an afternoon order halting departing traffic at US airports. The FAA's initial advisory was signed at 3:54 p.m. Eastern, with an event start time of 3:53 p.m. A later advisory identified the reason as a communications failure.

Homeland Security Secretary Markwayne Mullin told reporters that officials had acted as a precaution following a telecommunications outage affecting the FAA.

"There is no indication as of yet that this was a nefarious attack," he said.

Mullin said investigators were examining the cause and that restoring communications and ensuring passenger safety were immediate priorities.

American said aircraft already in the air could continue to their destinations. The FAA's initial order said inbound international flights would be managed individually.

A ground stop holds aircraft at their departure airports rather than ordering every aircraft already airborne to land immediately.

--IANS

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