Scott Morrison says he has pressed Atagi to change its advice on AstraZeneca

Scott Morrison has appealed for a change in official health advice for the AstraZeneca vaccine, saying the latest outbreak requires a new risk assessment to get more people vaccinated.

The prime minister, who has been on the defensive over the government’s handling of the troubled vaccine rollout, said on Wednesday that his “constant appeal” to the Australian technical advisory group on immunisation (Atagi) was to alter its advice to encourage more people to take the AstraZeneca shot.

“It’s a constant appeal, I can assure you,” Morrison said.

“The situation Australia faces should be managed on the balance of risk, as Atagi has said to me in the past. Well, it’s for them to now constantly reconsider how that balance of risk applies and provide their advice accordingly.”

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With more than 13 million Australians in lockdown, the premiers of Victoria and New South Wales have been urging the federal government to urgently boost vaccine supplies, saying the lack of doses is hampering their ability to protect their residents and claw out of protracted lockdowns.

Currently, the AstraZeneca vaccine is only recommended for those over the age of 60, with Pfizer described as the “preferred” vaccine for everyone else. Because of limited supplies, the Pfizer vaccine is currently only available for those between 40 and 60.

Atagi’s current advice is that the benefits of vaccination with AstraZeneca “strongly outweigh the risks of adverse effects” for those over 60 and that “vaccination is essential” for this group in the context of an outbreak.

In an outbreak where Pfizer supply is limited, adults younger than 60, “should re-assess the benefits to them … versus the rare risk of a serious side effect”.

Morrison told reporters in Canberra he had not spoken directly to Atagi’s co-chair, Prof Allen Cheng, about changing the advice, but Atagi was not “in any doubt” about the government’s view.

“When I spoke to Allen Cheng about these issues when he was chairing Atagi, and he was presenting to us on those matters, I relayed those sentiments at that time. And so, I need them to get on and do their job. We’ll get on and do our job.”

In a statement, Cheng said Atagi was “closely monitoring local and international data on thrombosis and thrombocytopenia syndrome (extremely rare blood clots) and the use of AZ vaccine.

“Currently, Atagi meets weekly to assess the latest safety data and local epidemiology, consider its risk-benefit assessment for the use of AZ, and provide independent advice to government,” he said.

Labor senator Katy Gallagher, a former chief minister of the ACT, questioned the safety of the prime minister’s press conference at the Lodge on Wednesday.

But an ACT Health spokesperson said requests from parliamentarians for exemptions to quarantine were referred to the commonwealth government and the health department relied “on the employer to determine what is essential work”.

Guardian Australia understands Morrison’s press conference was approved by the commonwealth chief medical officer.

ACT public health orders require people who are self-isolating not to leave their premises and not to allow others in.

Earlier on Wednesday, the NSW premier, Gladys Berejiklian, said the state needed to boost the vaccination rate before it could move beyond lockdowns.

She said the amount of vaccination was something beyond the NSW government’s control, but once doses arrived from the federal government, “they will be going into arms”.

The health minister, Brad Hazzard, said the state had plenty of the AstraZeneca vaccine, but Pfizer doses were “vastly under supplied”.

“We have actually done as much as humanly possible. The issue is we need more vaccine, we need more Pfizer,” he said. “We can’t get enough Pfizer to actually fill up all the facilities we’ve done.”

The Victorian premier, Daniel Andrews, has also been critical of “supply problems”.

Morrison suggested the government was attempting to increase its supply of the mRNA vaccines on order, including through Pfizer and Moderna, but he said Australians should get vaccinated with the available supplies of AstraZeneca after taking medical advice.

“My message is that people should be getting vaccinated as soon as possible with the vaccines available … And that is what I think is in Australia’s public health interest,” Morrison said.

Morrison commended Victoria for distributing AstraZeneca through its state-run vaccination hubs, but said he was not sure if an extra 150,000 doses of AstraZeneca given to the NSW government “has actually been utilised”.

NSW has so far administered 100,000 AstraZeneca doses through its state clinics, compared with 400,000 in Victoria.

“I would like to see more AstraZeneca vaccines being distributed through the state-based clinics like Victoria has been able to achieve, Morrison said.

He dismissed suggestions the government could have a different official position on AstraZeneca at odds with the independent advisory body, despite Atagi telling Guardian Australia its remit was purely to provide advice.

“Are you suggesting that the government when advised by the technical and advisory group on immunisation, some of the most senior level scientific medicos in the country, tell the government that the preferred vaccine for people of particular ages is 50 and then they changed it to 60, that the government should refuse that advice?” Morrison said.

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The prime minister has sought to shift criticism of the troubled vaccine rollout onto the independent advisory board.

Labor’s health spokesman, Mark Butler, said Morrison was putting unfair pressure on Atagi and dodging responsibility for the “terrible failures” of the vaccine rollout.

“Australians want their leaders to fess up when they fail or make a mistake and they’ll forgive that if they see honesty from their leaders and a change of tack,” Butler told the ABC.

In a round of interviews on Adelaide and Melbourne radio on Wednesday morning, Morrison came under pressure to apologise for problems in the vaccine rollout and to explain earlier remarks that the program was “not a race”.

A million doses of vaccine have been delivered within seven days for the first time in the past week, bringing the total number of vaccinations administered to 10,470,033.

This means that more than 14% of the adult population are now fully vaccinated and 36.12% have received one dose.