Daniel McCulloch and Matt Coughlan
(Australian Associated Press)

Australians desperate to see family and friends interstate are being urged to let health authorities contain coronavirus outbreaks first.

The Northern Territory could refuse visitors from some parts of the country for another year, while Western Australia warns its borders could remain closed for 18 months.

Christmas in Queensland is also looking unlikely for anyone south of the border.

The closures are creating immense stress for many families who live in different states and people with sick or dying relatives they cannot get to.

Deputy Prime Minister Michael McCormack acknowledged it was an absolutely awful situation for many people.

But he also urged people wanting to take interstate holidays not to get ahead of themselves.

“The virus has to be contained and minimised,” Mr McCormack told the Nine Network on Wednesday.

“State premiers and chief ministers have made the border closures to protect their own jurisdictions.”

Victoria has reported another 21 deaths and 410 new infections.

The record number of deaths takes the national toll to 352.

Growing virus clusters in Sydney and on the NSW south coast have forced the closure of more schools and businesses.

Tasmania has recorded its first case in 20 days, a man in his 60s who returned from Melbourne after medical treatment.

Meanwhile, the ACT chief minister has hatched a plan so Canberrans stuck at the Victorian border can drive home.

Andrew Barr hopes the NSW government accepts his idea to let the stranded people travel under police escort with a short stop north of Gundagai.

Hotel quarantine arrangements in Melbourne have created another flashpoint between the federal and state governments.

Defence Minister Linda Reynolds has accused the Victorian government of rejecting repeated offers for troops to help with security.

Victorian Premier Daniel Andrews told a parliamentary inquiry Australian Defence Force personnel were not offered to the state government.

But Senator Reynolds scotched his claims, saying Victorian authorities advised the federal government in late March no help was needed with hotel quarantine.

Breaches in hotel quarantine are believed to be behind Victoria’s second wave, which has put the state into the nation’s harshest lockdown.

Acting Chief Medical Officer Paul Kelly said the nation was still performing well internationally despite the tragic deaths.

He said the average age of people who had died nationally was well over 80, with many victims aged in their 90s.

“Our death rate within the total 21,000 cases we have had is extremely low and there have been very few cases outside of aged care,” he said.

“It’s a tragedy to lose a loved one but really, there have been very few deaths in comparison to other countries.”