Australia allows 6,315 citizens and permanent residents to return each week.
But with thousands stranded overseas and pressure growing, Morrison said Tasmania state has agreed to provide accommodation for the additional 450 people to undergo quarantine on the island.
"We’re working every option to help as many Australians return home as quickly as possible,” Morrison said in an emailed statement.
Australia’s second Covid-19 outbreak started after people returning from overseas in Victoria state spread the virus to hotel workers while undergoing a mandatory 14-day quarantine, who in turn passed the virus in the community.
After daily cases in the state peaked at more than 700 infections, Victoria placed nearly 5 million people around Melbourne into a stringent lockdown for more than 100 days.
The measures have slowed the spread of the virus and Victoria on Saturday reported its eighth straight day without a Covid-19 case.
Australia has recorded just over 27,600 novel coronavirus infections and 907 deaths, far fewer than many other developed countries.