WASHINGTON D.C.: The U.S. Transportation Department said it could require airlines to offer passengers a refund if their flight schedules or itineraries change significantly.

Under the proposed rule, even travelers with nonrefundable tickets would be compensated. Further, airlines must provide refunds if their departures or arrival times change by at least six hours for an international flight, or three hours or more for a domestic flight.

If an airline changes a passenger's departure or arrival airport, adds stops to their itinerary, or causes "a significant downgrade" in the travel experience by switching to a different type of plane, then refunds must also be given.

After being flooded with complaints by passengers whose flights were canceled or changed and could not get refunds, the department decided to review its rules on refunds.

Airlines and ticket agents could also be required to provide vouchers with no expiry dates for passengers who cannot travel during a pandemic for health reasons or because of closed borders.

Airlines, which prefer to hand out travel vouchers instead of refunds, will likely oppose the proposal.

Currently, there is no official definition for cancellation or significant change, therefore airlines have challenged the Transportation Department's authority to force them to pay refunds.

In a statement, Transportation Secretary Pete Buttigieg said, "When Americans buy an airline ticket, they should get to their destination safely, reliably, and affordably. This new proposed rule would protect the rights of travelers and help ensure they get the timely refunds they deserve from the airlines."

In 2020, complaints filed by consumers with the department rose nearly seven times from the previous year, and 87 percent concerned refunds.