Morrison admits all Australians may not be vaccinated by end of year due to ‘many uncertainties’

Scott Morrison says there are too many uncertainties to set a new target for vaccinating Australians against Covid-19, as the government moves to shore up confidence in the trouble-plagued rollout.

The prime minister said while he hoped all Australians could have a first dose of vaccination by the end of the year, Morrison said on Sunday there was no new timetable to replace the previous October target.

It is the latest retreat on the government’s vaccine rollout strategy which has been beset by delays, confusion and supply challenges since Australia first locked in agreements with manufacturers last year and declared the country “at the front of the queue”.

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“The government has also not set, nor has any plans to set any new targets for completing first doses,” Morrison said on Facebook on Sunday afternoon.

“While we would like to see these doses completed before the end of the year, it is not possible to set such targets given the many uncertainties involved.

“We will just get on with the job of working together to produce, distribute and administer the vaccines as safely and efficiently as possible.”

Following a meeting of national cabinet on Friday, the commonwealth and state governments agreed to release daily data reports on the progress of the vaccination rollout, responding to concerns about a lack of transparency and confusion among the states about vaccine supplies.

Sunday’s figures show that across Australia about 1.16m vaccinations have now been dispensed, with about half delivered by the commonwealth through the GP network and in aged and disability care, and the other half delivered through state vaccination hubs.

In the wake of a government revision to the vaccination program for under-50s based on an extremely rare blood-clot side effect linked to the AstraZeneca vaccine, the health minister, Greg Hunt, also moved to reassure Australians that the program was “safe and effective”.

“These vaccines are safe and effective and we simply follow the advice on administration of our medical experts. That has kept Australians safe and we will continue to provide those updates,” Hunt said.

“Our message is simple, please continue to get vaccinated, it’s safe, it’s effective, it can save your life and it can save the life of your friend, or your family, or your neighbour.”

Related: What does Australia’s new advice on the AstraZeneca Covid vaccine mean and what is the risk?

He also addressed a report in the Sydney Morning Herald which said some doctors feared they could be liable if patients suffered serious or fatal side effects from the AstraZeneca vaccine.

He said doctors, who were at “the heart of the program”, were flocking to sign up to the vaccination rollout, with 1,000 GP practices set to sign up this week, bringing the total to more than 4,000. Following the changed guidelines over the AstraZeneca vaccine, Hunt said clear advice had been provided to the Australian Medical Association and the Royal Australian College of General Practitioners that they were indemnified by government.

“I want to make something very, very clear. Australia already has vaccine indemnity agreements in place. The AMA and College of General Practitioners have clear advice in writing from the government to that effect and they also have updated informed consent material so no doctor need worry. I am saying this on behalf of the government but also on behalf of our legal advice, no doctor need worry.”

Earlier on Sunday, trade minister Dan Tehan said the government was aiming to have all Australians vaccinated by the end of the year, but warned there were “a lot of unknowns” that could further derail the troubled rollout.

After announcing a major shift in the government’s vaccine program last week following updated health advice on the AstraZeneca vaccine, the government said its initial October target would not be realised.

However Tehan said on Sunday that the government was hopeful that all Australians could receive at least one dose of the Covid-19 vaccine by the end of the year.

“That is definitely the aim, that is the goal we have set: trying to have all Australians have a dose by the end of the year,” Tehan told Sky News.

“[But] when you are dealing with a pandemic, there is a lot of unknowns and you have just got to make sure you set your goals and are prepared to adjust those as things occur.”

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Health officials have recommended people aged under 50 be offered alternatives to the AstraZeneca vaccine because of the extremely rare chance of blood clot side effects, saying the Pfizer mRNA vaccine is “preferred” for this age cohort.

The prime minister, Scott Morrison, said the change would require a recalibration of the vaccine timetable but refused to provide a guarantee that all Australians would be offered a jab by Christmas.

Tehan also revealed he will be travelling to Europe to discuss vaccine supply deals, with meetings scheduled with officials from the European Union, France, Germany and the World Trade Organisation.

Australia and the European Commission engaged in a diplomatic spat last week over vaccine exports from Europe, which have been stymied by the European Union’s export controls.

“I will also be meeting the director general of the World Trade Organisation to talk about what we can do to ensure supply of the vaccine, not only for Australia, but globally,” Tehan said.

“Now it’s just a matter of making sure that we get all the contracts honoured, and then we make sure that we can distribute the vaccines right across the nation.”

The shadow health minister, Mark Butler, accused the government of being too reliant on the AstraZeneca vaccine, saying the “difficult” situation was one of the government’s own making.

“Australia was already way behind schedule in the vaccine rollout, not in the top 100 nations in the world and a bad situation has been made far worse by these unforeseen events around the AstraZeneca vaccine.”

Butler also said the government needed to ensure all Australians had a dose by Christmas, with the opening up of the economy dependent on it.

Related: Scott Morrison spun a Covid vaccine story the public believed – and then it fell apart | Paul Karp

“We really can’t have a situation where vaccines are rolling out into next year which seems to be the prime minister’s thinking,” Butler told the ABC’s Insiders program.

“This is not just a question of the strength of our economic recovery – it’s also a question about the health of our population.”

Following the changed advice on the AstraZeneca vaccine, the government announced it had secured an extra 20m doses of the Pfizer BioNTech Covid-19 vaccine for the last quarter of the year.

This comes on top of 20m previously contracted Pfizer vaccine doses which the health minister, Greg Hunt, has said will begin ramping up through distribution networks this month.

Hunt said Pfizer had indicated “that we will see an expansion in April”, up from the current figures of “approximately 130,000-plus a week”. He also expected to see “quite a significant expansion in May” and then “a near-doubling” in July.