There are 15 new community cases of COVID-19 in Sydney on Monday.
All of the cases are linked to the existing Northern Beaches cluster, New South Wales Premier Gladys Berejiklian said. Over the past 24 hours more than 38,000 people have been tested for the virus. The new cases bring the cluster to at least 83 cases.
It comes after 30 new cases were announced on Sunday, 28 of which are directly linked to the existing cluster.
Premier Berejiklian offered reassurance that health officials have a plan, while praising NSW's contact tracing.
"I believe, [NSW has] one of the best if not the best contact tracing team on the planet."
But Berejiklian said, unfortunately, one day's results don't "tell us it's a trend".
"Obviously, we have halved the number of cases overnight, but in a pandemic, there is a level of volatility, so we'll closely monitor what happens."
She also warned against complacency after revelations the new cases had visited several places around Syndey.
"We know what the high-risk areas of transmission are and we ask people to respond accordingly. Don't think that you're immune.
"This can affect any of us, and we know from the cases not just in the last few days, but previously, how absolutely contagious this virus is."
Earlier on Monday, health officials released a list of locations that had been visited by confirmed cases of the coronavirus. The venues included a nail salon, mall and cafe, along with a bar and bus route.
On Sunday night Victoria closed its border to Greater Sydney, declaring it a 'red zone'.
All Greater Sydney residents were also placed under tighter restrictions, with no more than 10 guests allowed in a household, while social distancing curbs have also been placed on hospitality venues.
The growing cluster has continued to raise questions over a potential trans-Tasman travel bubble. The New Zealand Governmern has said it would only proceed if Australia goes 28 days without a local case.
In a statement on Sunday, New Zealand's Ministry of Health said it was closely monitoring the situation in NSW.
"Commencement is dependent on no significant change in the circumstances of either country. Decisions on whether or not to proceed with a travel bubble will occur in the new year and we will assess the situation at that point."
"We're monitoring the situation closely, but it's too early to make any decisions based on the current community cases in New South Wales."
