While the national rate for fully-vaccinated over 16s has passed 80 per cent, immunisation rates among Indigenous communities are lagging.

The prime minister said there was still a long way to go to bridge the vaccination gap.

“There is a challenge in Indigenous communities, particularly in (WA and Queensland),” Morrison told Newcastle radio.

“In NSW the Indigenous rate of vaccinations have been lifting and there’s been some rally good work there, but that is a challenge we find all around the world.”

It comes as NSW recorded 187 new COVID-19 cases of in the past reporting period, with seven deaths reported.

There were 1126 new infections in Victoria and five deaths.

Meanwhile, GPs and pharmacies across the country will rollout Pfizer vaccine booster shots as part of the national rollout which began on Monday.

The third Pfizer vaccine dose has already been made available to aged care and disability care residents since it was approved by the Therapeutic Goods Administration.

Health Minister Greg Hunt said the booster program was already off to a flying start.

“We are already at 173,000 people who have had their boosters,” Mr Hunt told the Seven Network on Monday.

“GPs, state clinics, commonwealth clinics, Indigenous medical centres, aged care and disability have been vaccinating people with boosters, so it’s a great start.”

The health minister said work was still under way to determine whether booster shots would needed each year like the flu shot or if a third dose would provide enough protection.

“A booster dose, six or more months after the second dose, will make sure that the protection from the first doses is even stronger and longer lasting,” Mr Hunt said.

The Therapeutic Goods Administration is still considering data from Pfizer as to whether to approve its vaccine for children aged five to 11.

Hunt said Australia would be one of the first countries in the world to approve a vaccine for the age group but said a full and thorough assessment of data was needed before it was given the green light.

“Our kids are far less likely to get (COVID) or in particular to have serious complications,” he said.

“But we want to make that vaccine available and we will be able to do that as soon as the medical regulators approve it.”

Meanwhile, Northern Territory Chief Minister Michael Gunner extended the three-day lockdown in Greater Darwin by 24 hours until midnight on Monday to allow time for much-needed contact testing.

Katherine also went from a lockdown to a lockout on Sunday afternoon, with only vaccinated people permitted to move about freely the community.