A Virgin flight that was cleared for take-off was forced to abort when a Qantas plane began to cross the runway in the third near-miss at Sydney Airport.

The Australian Transport Safety Bureau said it was investigating the incident involving two Boeing 737s on Sunday.

It was the same day as another near-collision involving Jetstar and Qatar Airways aircrafts on the tarmac.

In the latest drama, Virgin Australia flight VA555 was bound for Perth when it was cleared for a “full-length takeoff” on runway 34L about 10am on Sunday, the transport bureau said.

“As the crew applied thrust for takeoff, they observed the Qantas 737 begin to cross the runway ahead of them from taxiway Lima,” the ATSB said.

The Qantas QF728 flight, heading to Ayers Rock Airport, was also cleared to cross the runway and was about 1200 metres ahead.

To prevent a potential collision, the Virgin Australia pilots reacted by reducing thrust and stopping the aircraft on the runway.

“At the same time, [Air Traffic Control] broadcast a cancellation of the take-off clearance,” the transport safety investigator said.

“Once the Qantas 737 was clear of the runway, the Virgin Australia 737 was re-cleared by ATC to commence take-off.”

The aircraft were not close to one another. The Virgin plane stopped about 1 kilometre from the intersection.

It’s the third incident to emerge at Sydney Airport in less than three weeks as the transport hub struggles with staff shortages.

Hours earlier on Sunday, a Jetstar flight preparing to depart Sydney Airport for the Gold Coast had almost collided with a Qatar Airways plane.

The Jetstar Airbus 320 pilot was forced to brake suddenly to avoid a collision with the Qatari plane on the tarmac.

The Qatar Airways Boeing 777, which was not carrying any passengers, was being towed by an aircraft tug. It received minor damage.

The Jetstar flight was cancelled and passengers were re-booked on other services to the Gold Coast later on Sunday.

Air traffic control was reportedly operating under restricted hours in Sydney between 6-8am on Sunday, reducing the number of flights arriving and departing due to staffing shortages.

Sunday’s incident followed delays to more than 150 flights passing through Sydney on Saturday as airport operations struggled due to a lack of staff.

Airservices Australia, which oversees air traffic control at the hub, had been unable to roster enough staff for three consecutive days, Airlines for Australia and New Zealand chief executive Stephen Beckett told ABC TV.

Sydney Airport also faced significant issues on Friday, when more than 120 flights were delayed.

NSW Premier Chris Minns stressed the importance of the airport operating at full capacity.

“We’re hopeful that there’s a plan in place to recruit more people for a highly specialised but very important job … we’re opening a brand new airport in the not-too-distant future, so there’ll be even more strain on that service than there is today,” he said.

“I know it’s hard to employ people, particularly for these specialised services, because we’ve got a very tight labor market.

“But this isn’t a nice-to-have – it’s a must-have.”

-with AAP