Advice that a large number of Canberrans had left the ACT for the South Coast after the ACT announced restrictions contributed to NSW's statewide lockdown decision, Premier Gladys Berejiklian says.
Ms Berejiklian said the number of people who had moved from the ACT to southern parts of NSW was a concern, and formed part of health advice to lock down NSW entirely.
"Yesterday was an absolute wake-up call," Ms Berejiklian said on Sunday.
NSW recorded another 415 cases of COVID-19 in the community on the first full day of a statewide seven-day lockdown, which was haphazardly announced on Saturday afternoon.
Four people died and 62 people remained in intensive care.
NSW chief health officer Dr Kerry Chant said she could not describe her level of concern if cases were not driven down.
"It has been so pleasing [seeing] the vaccine numbers increase, because every person that is vaccinated provides a little bit of protection. But ultimately, we also have to decrease our interactions with others if we are going to spread of this disease," Dr Chant said.
NSW Deputy Premier John Barilaro said the "threat that's coming out of Canberra" put "pressure on the southern part of this state".
Mr Barilaro said a statewide lockdown was now the safest option for NSW.
"We've known, as we've seen already with what we did in Orange, a sharp, hard lockdown early has meant we've seen freedom come back to regional NSW even sooner," he said.
Meanwhile, Victoria recorded 25 new cases of COVID-19, from more than 32,200 tests.
Of the locally-acquired cases, 21 are linked to known outbreaks and 12 have been in isolation throughout their infectious period. There are now 185 active cases.
Victorian Premier Daniel Andrews said an extra 84,000 vaccine appointments would be made available from Sunday.
"The more people that are vaccinated faster, then the greater benefit to all of us," Mr Andrews said.
Queensland reported no new locally acquired cases of COVID-19 on Sunday.
Queensland Premier Annastacia Palaszczuk warned the Indooroopilly cluster of 143 cases was unlikely to have fully exhausted itself.
"We are not out of the woods yet - if you have any symptoms, please go and get a test, that's critical," Ms Palaszczuk said on Sunday.
