Australian airline Qantas announced Tuesday it will furlough 2,500 workers as coronavirus outbreaks and regional lockdowns pummel demand for flights.

Pilots, cabin crew and airport workers from Qantas and its low-cost affiliate Jetstar will be sent home without pay from mid-August for an estimated two months, the firm said.

"This is clearly the last thing we want to do, but we're now faced with an extended period of reduced flying and that means no work for a number of our people," CEO Alan Joyce said in a statement.

Qantas said the airline had gone from operating almost 100 percent of its usual domestic flying capacity in May to less than 40 percent in July due to coronavirus restrictions.

Most of the affected staff are based in New South Wales, a state that is largely cut off from the rest of the country and the world by travel restrictions.

A lockdown in the country's largest city, Sydney, is now in its sixth week and is likely to last for at least another month.

Qantas and Jetstar have already stood down thousands of international aircrew since early 2020, with Australia's borders remaining closed to most overseas travellers.

The country's third-biggest city, Brisbane, is currently under stay-at-home orders while other states have only recently emerged from lockdowns.

Qantas said staff will be paid for two weeks before the change comes into effect.

"Based on current case numbers, it's reasonable to assume that Sydney's borders will be closed for at least another two months," Joyce said.

"We know it will take a few weeks once the outbreak is under control before other states open to New South Wales and normal travel can resume."

Qantas, which previously said it had seen an Aus$11 billion (US$8.1 billion) plunge in revenue during 2020, embarked on a cost-cutting blitz last year that included grounding planes and restructuring.