Ten new cases were reported by NSW Health on Tuesday, with seven of these detected after the reporting period's 8pm cut off on Monday night.
These cases will be included in Wednesday's numbers.
Mask wearing is now mandatory in indoor areas across all of Greater Sydney.
NSW Premier Gladys Berejiklian said mask wearing will also be extended an additional week from Thursday when it was set to end in previously selected councils.
“That means excluding the Central Coast and excluding the Hunter, there will be a requirement to adhere to that compulsory mask wearing indoors for hospitality workers when we are going shopping, going grocery shopping, going to events inside,” she said.
“It is only when you are eating or drinking indoors at a venue that you can’t or shouldn’t wear a mask.
“In every other circumstance, if you live or are in Sydney, you must wear a mask for another week beyond Wednesday midnight.”
Wollongong and Shellharbour areas will also have masks mandatory on public transport.
The premier cited “an increased level of concern” over how transmissible the virus is.
Could there be a lockdown?
The premier was asked if health authorities were considering a lockdown to which Ms Berejiklian said she was following the advice of Chief Health Officer Dr Kerry Chant.
“At this stage because all but one case is linked to an existing case and that case was only discovered a few hours ago, that gives us a degree of confidence that what we have asked people to do matches the risk that is there at the moment," she said.
"If that changes, if we suddenly have a number of unlinked cases and if we suddenly have them outside the geographic region they are concentrated in that will obviously adjust the health advice and we will respond to that."
She added Dr Chant "foresaw" more cases in the cluster in household contacts.
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