BLAGNAC, France: Airlines around the world are facing mounting disruptions after Airbus ordered immediate repairs to 6,000 A320 aircraft, grounding more than half the global fleet at the start of a peak U.S. travel weekend.

The mandatory fix, outlined in a bulletin to carriers, primarily requires reverting to an earlier software version, and aircraft cannot return to service until the update is completed. Several carriers warned of delays and cancellations as they work through the recall.

Below is a list of significant operational impacts reported by airlines as of 0733 GMT, in alphabetical order:

Aer Lingus

The Irish airline said a limited number of planes were affected.

Air France

The carrier cancelled 35 flights.

Air India

Of 113 aircraft requiring the fix, 42 have been updated. Some delays are expected, but no cancellations.

Air India Express

Twenty-five aircraft need software updates, India's aviation regulator said.

Air New Zealand

The airline expects some cancellations.

American Airlines

The world's largest A320 operator warned of delays but reduced the number of aircraft requiring updates to 209 from an earlier estimate of 340.

ANA Holdings

The Japanese carrier cancelled 65 flights on Saturday.

Avianca

More than 70 percent of the Colombian airline's fleet is affected, leading to "significant" disruption over the next 10 days. Ticket sales for travel through Dec. 8 are paused.

Delta Air Lines

The U.S. carrier expects limited operational impact.

flynas

The Saudi budget airline anticipates some delays.

IndiGo

India's largest airline has completed fixes on 143 of 200 aircraft, the regulator said. Some delays are expected.

Korean Air

Work on the 10 affected aircraft will be completed by Sunday morning.

Latam Airlines

A limited number of aircraft require updates.

Lufthansa

The German carrier expects a small number of cancellations or delays over the weekend.

Turkish Airlines

Eight A320s will return to service once required actions are completed.

United Airlines

The airline expects minor disruption after six aircraft were identified.

Viva

The Mexican carrier said its fleet will be affected, but no timeline is set for completion.

Wizz Air

The budget airline said all required updates were implemented overnight and no further disruption is expected.