Dozens of flights have been cancelled or delayed due to an air traffic controller shortage at Sydney Airport.
Airservices Australia has confirmed it is experiencing staff shortages in Sydney today, triggering delays for all airlines.
Virgin Australia said it expects flights across its network to be impacted.
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At least 25 flights scheduled between 6.30am and 9.40pm today have been cancelled, according to FlightRadar.
It is mostly impacting domestic routes.
Qantas, Virgin and Jetstar are among the airlines with cancelled departures.
Airservices said it had informed airlines of staffing issues impacting flights at Sydney Kingsford Smith Airport.
"Airservices has briefed airlines on the need for air traffic controllers to implement spacing intervals for aircraft arriving and departing Sydney today to safely manage operations while a number of our local staff are on short-notice sick and carers leave, some of whom have been covered through our resilience measures," a spokesperson said.
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"We will keep delays to a minimum and apologise for any impact to our customers and the travelling public.
"Airservices is continuing to recruit to ensure we have additional staff available as an on-call capability to cover these kinds of short notice absences."
More to come.