Qantas workers have been warned that ongoing COVID-19 border closures across Australia could mean the airline is forced to stand down employees.

In a message to staff, airline CEO Alan Joyce lamented “frustratingly familiar challenges” for his team as more than 14 million people in NSW, Victoria and South Australia were subject to stay-at-home orders.

“We’re not at the point of requiring stand-downs in our domestic operations at this stage,” he wrote in an email to Qantas staff on Thursday.

“But to be honest, we can’t rule it out if multiple states keep their borders closed for extended periods.”

Mr Joyce said he wanted to “share his thinking” as Qantas services took a hit, with numerous cancelled flights.

“NSW is a key part of the Qantas and Jetstar network, so that lockdown has already seen our total domestic flying fall from 90 per cent of pre-COVID levels to around 60 per cent,” he wrote.

“When you add in the Victorian and now South Australian lockdowns, our total flying drops below 40 per cent.”

The Australian Services Union used news of the downturn to call on the federal government to urgently reinstate JobKeeper support measures.

“We need to recognise that the COVID-19 crisis before us now is as bad, if not worse, than last year’s lockdown and economic fallout,” the union’s Emeline Gaske said.

“The livelihoods of thousands of Australian workers and their families now hang in the balance and JobKeeper is the only thing that will save their jobs.”

Ms Gaske said 78 per cent of Qantas workers had been totally reliant on JobKeeper during the 2020 COVID lockdown, and 72 per cent said they would not have been able to support their families without the payment.

“The federal government must accept that the current disaster payment income support payment is insufficient to support Australian workers or prevent a major economic downturn,” she said.

The federal government insists that national wage subsidies will not be reintroduced.

A weekly disaster payment of between $375 and $600 has been made available to people suffering hardship during outbreaks.

In mid-2020 almost 15,000 Qantas staff were stood down without pay or on forced leave as the national carrier moved to shed 6000 jobs and slash costs to weather the coronavirus storm.

The Transport Workers Union, which also represents Qantas workers, has calculated that the airline has already received at least $2 billion in government support.

It cited submissions from Qantas to a Senate inquiry that showed it had collected $726 million in JobKeeper up to the end of December, as well as $488 million in financial support for aviation.

In addition, the union told the ABC that Qantas and other airlines had been subsidised through ongoing support for aviation as well as the federal scheme offering half-price airfares to many top domestic tourist destinations.

In his latest memo, Mr Joyce was optimistic.

“Unlike last winter, there’s now a COVID vaccine rolling out, and that means this cycle of restrictions and lockdowns will break.”

-with AAP