The head of Australian Border Force says there would be no point in sealing off Australia, as the federal government escalates its travel warnings to an unprecedented level.
Prime Minister Scott Morrison announced on Wednesday morning Australia would upgrade its travel advice to level four - "do not travel" - for every country around the world for the first time in history.
Level four is the highest possible travel advisory and warns that the Australian government may not be able to assist citizens abroad if they run into trouble. It also advises that travel insurance policies may be void and travellers' health and safety is at extreme risk.
"The travel advice to every Australian is 'Do not travel abroad'. Do not go overseas. For those who are thinking of going overseas in the school holidays, don't," Mr Morrison said.
Chief Medical Officer Brendan Murphy said said he expected imported cases of the virus to "drop significantly" as international travel declined.
But Border Force commissioner Michael Outram said while visitors to Australia will need to self-isolate for 14 days, a hard closure of borders would be of little benefit.
"We don't want to stop all flights to Australia. We don't want to seal ourselves off," Commissioner Outram told media on Wednesday morning.
"We want to keep ports moving. This is really important because we want to keep our ports moving obviously a lot of goods are coming through those ports, a lot of exports still going on, bulk and other things to containers so keeping those ports moving is really important and we'll continue to do so.
"I don't think there's much benefit in sealing off Australia, but what we've done is...significantly reduce the number of people incoming to Australia. All unessential travel to Australia has ostensibly been turned off."
Virgin has announced it will suspend international flights from March 30 to June 14, while Qantas cut 90 per cent of its international flights on Tuesday.
More than 20 international flights scheduled to arrive in Australia on Tuesday were cancelled, Commissioner Outram said.
International passenger numbers to Australia on Monday was down by nearly 5000 people on the week before.
Commissioner Outram said Border Force were preparing for an influx of passengers returning home. Planes would be met by agricultural Border Force officers and there would be health workers at airports to do "in-house readings".
An extra 25 officers were sent to Sydney Airport on Sunday night in the aftermath of the new travel restrictions, which required anyone entering the country to isolate for 14 days.
"We've had to move people around as you can imagine with something like this," Commissioner Outram said.
"We've had to move people from into cargo into airports and back into cargo and other areas of our organisation."
Commissioner Outram said no Border Force officer had been struck down with the virus, despite interacting with millions of passengers over the past two months.
About a dozen officers have been tested so far and all were cleared.
It came as Deputy Prime Minister Michael McCormack announced a $715 million relief package for Australian airlines hit by the virus, waiving government charges on aviation fuel excise, Airservices charges on domestic airline operations and domestic and regional aviation security charges.
Airlines will receive a $159 million shot-in-the-arm immediately with reimbursement of applicable charges paid by domestic airlines since 1 February 2020.
But Regional Express Airlines has warned the company could fold within months without greater government support.
And while some remote communities will be locked down, Mr Morrison said domestic air travel was a "low risk".
"We have not seen a lot of evidence of people contracting this virus on aircraft. It is when they have arrived, or where they have brought it from," Mr Morrison said.
"It is not about going on a plane or not, it is about where you are going to."
- For information on COVID-19, please go to the federal Health Department's website.
- You can also call the Coronavirus Health Information Line on 1800 020 080
- If you have serious symptoms, such as difficulty breathing, call Triple Zero (000)
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