The prime minister's restraint in attacking the Andrews Labor government evaporated on Tuesday as he faced sustained questioning over aged care.

"The protective measures that were put in place and built up as part of that national strategy, employed by all states and territories, have failed in Victoria," Mr Morrison told parliament.

"The testing, the tracing and the quarantine arrangements have proven to be unacceptable and led to what we have seen with community outbreak in Victoria."

He said the government would do everything possible to help Victoria stabilise infection rates and lift restrictions.

Health Minister Greg Hunt also took the gloves off, noting 95 per cent of the increase in Australian cases since June had been in Victoria.

"Overwhelmingly from one city, and overwhelmingly from one part of one city," he told MPs.

Mr Hunt said 99 per cent of deaths since June 1 were in Victoria.

"So this is very much sadly and tragically the issue of one city in one state."

Mr Morrison rubbished senior counsel assisting the aged royal commission's use of a statistic showing 70 per cent of Australian coronavirus deaths were linked to the sector.

"The evidence provided by the secretary of health was very clear that that was a use of statistics which was highly misleading," the prime minister said.

The government argues Australia has performed well by international standards and sought to shift the responsibility for managing the health response to Victoria.

Aged Care Minister Richard Colbeck faced a second day of pressure in parliament over his failure to remember the number of nursing home deaths.

Labor is demanding Mr Morrison sack the embattled minister, who emphatically denied he had been stripped of responsibilities because of his performance.

Opposition Leader Anthony Albanese said Senator Colbeck had failed to prepare the sector for further outbreaks after the disease tore through two Sydney nursing homes.

There have been 335 coronavirus deaths linked to aged care nationally, with 295 in Victoria.

More than three-quarters of Australians believe authorities failed to prepare a coronavirus strategy for aged care outbreaks, according to an Essential poll released on Tuesday.

About 70 per cent said long-term underfunding of the sector had worsened the impact of coronavirus in aged care.

Asked who was to blame for aged care outbreaks, 42 per cent of the 1068 survey respondents pointed the finger at aged care providers.

State governments were at 30 per cent, ahead of the federal government at 28 per cent.

Just 49 per cent of people correctly identified the federal government is responsible for funding and regulating private aged care.

Australian Associated Press