Health Minister Greg Hunt has declared the Omicron variant is nearing its peak across several infection hotspots as states continue to grapple with rising case numbers.
NSW recorded an increase in people hospitalised with COVID-19 with 2,816, a jump from the 2,712 recorded on Sunday.
But the number of people in hospital in Victoria fell to 998, down from 1,002 patients on Sunday and remained steady in Queensland at 863.
Mr Hunt said hospitalisation numbers were showing promising signs of stabilising after COVID-19 infections had soared during the Omicron wave.
"We’re seeing clear signs that this Omicron wave at least in NSW, Victoria and the ACT has peaked - South Australia had also had some promising signs," he told reporters.
He said this would help ease pressure on intensive care units.
"We've seen a decrease in case numbers significantly and we've seen a decrease in hospitalisation numbers of over 100 in Victoria and NSW."
"That, in turn, will have an impact on ICU and ventilation numbers."
There are 196 people in intensive care in NSW and 119 people in ICU in Victoria.
Another 24 people died in NSW with 15,091 new infections of COVID-19 - down from 20,324 cases on Sunday.
Victoria, meanwhile, has recorded 17 fatalities and 11,695 cases of the virus - a decrease from 13,091 infections on Sunday.
Queensland reported another 13 deaths and 10,212 cases and the ACT two deaths and 756 cases.
Mr Hunt's comments come as Australia's leading advisory group on vaccines gave the final approval to the Novavax vaccine.
The vaccine, the fourth to be approved in Australia for COVID-19, will be rolled out from 21 February.
People wanting to get the Novavax vaccine will need two doses spaced 21 days apart.
Mr Hunt said the protein-based vaccine would provide another option for vaccination - in particular for those facing potential reactions to other vaccines.
Elsewhere, Tasmania has reported 619 new COVID-19 cases, with the number of people being treated in hospital for the virus increasing by one.
Forty-one people in hospital have coronavirus, with 24 of those being treated for unrelated medical conditions, the state health department said.
Seventeen people are being treated for COVID-19, up from 16 reported on Sunday. Three patients are in intensive care.
South Australia reported another fall in COVID-19 infections, with 2,009 new cases on Monday, down from 2,062 on Sunday and 2,193 on Saturday.
The state has 294 people in hospital, including 29 in intensive care where six are on ventilators.
There were also two more deaths, a woman in her 40s and a man in his 70s, taking SA's toll since the start of the pandemic to 69.
The Northern Territory reported 286 new COVID-19 cases on Monday as
an Australian Medical Assistance Team and the military stepped in to help combat a remote Aboriginal community outbreak.
The cluster in Galiwin'ku on Elcho Island, 515km east of Darwin, has grown to 87 cases.
Western Australia reported 13 new local COVID-19 cases and two infections linked to travellers on Monday.
Of the locally acquired infections, 10 are linked to an outbreak in the southern Perth suburb of Coolbellup.
This includes eight household contacts and two close contacts.
A household contact from the Safety Bay cluster also tested positive and a person became infected after visiting the Willagee IGA supermarket.
An infection was also found in the Greater Bunbury region, about two hours south of Perth, and remains under investigation.
RATS supplies offered to concession cards holders
Monday marked the beginning of the rollout of free rapid antigen tests to concession card holders across the country.
More than six million Australians who have a concession will be eligible for 10 free rapid tests at pharmacies throughout a three-month period, with a limit of five in one month.
Mr Hunt said 16 million rapid antigen tests were expected to arrive between now and the end of July bolstering supplies of the tests.
"The advice that we have from the pharmacies is that there will be adequate supply going forward," he said.
However, Pharmacy Guild of Australia president Trent Twomey said supply shortages of the tests meant the rollout would be significantly impacted.
"We don't have enough today," he told the Nine Network on Monday.
"There are 6,000 community pharmacies in Australia and 804 pharmacies went live this morning. The majority will simply not be going live."