Sydney has avoided a lockdown despite Gladys Berejiklian saying NSW was in the "scariest" period since the COVID-19 pandemic began.
Despite widespread speculation that Sydney was on the brink of another lockdown, the premier held her nerve but flagged a police blitz to nab anyone defying tough new restrictions announced on Wednesday.
"Since the pandemic has started, this is perhaps the scariest period that NSW is going through," she told reporters on Thursday.
"It is a very contagious (Delta) variant but at the same time we are at this stage comfortable that the settings that are in place are the appropriate settings, but that is so long as everybody does the right thing."
NSW Chief Health Officer Kerry Chant said a lockdown wasn't required because there weren't large numbers of unlinked cases nor a backlog of contact tracing.
There were 18 new cases recorded from 48,402 tests in the 24 hours to 8pm on Wednesday, 13 of which were announced earlier.
Another six cases were detected after the 8pm cut off which will be included in Friday's official tally.
That means there's a total of 11 new cases linked to the outbreak that began in Bondi last week that now stands at 36 after rapidly spreading in Sydney's east before infiltrating other areas.
Of the new cases, all but one are linked to a known case or the Bondi cluster, with urgent investigations underway into how a man in his 40s caught the virus. He's the second man in as many days who has contracted the virus from an unknown source.
Ms Berejiklian revealed she had tested negative to the virus after one of her cabinet ministers tested positive, sending shock waves through NSW Parliament House.
Agriculture Minister Adam Marshall confirmed he has the virus after dining with three Nationals' colleagues on Monday night at an eastern Sydney pizzeria that was later declared a hotspot.
Trevor Khan, Steph Cooke and Ben Franklin have all since tested negative.
Mr Marshall issued a statement saying he had been isolating at his Sydney flat since Tuesday night and won't return to his Armidale home for at least 14 days. His staff are also in isolation.
Speaking to the ABC, Mr Marshall said he was physically fine and asymptomatic, but was concerned for everyone at parliament.
"It just highlights again everything that has been said about this new Delta variant is true," he said.
"The place where I caught it was a place where I had no physical contact with anyone at any time and yet I am now positive for COVID-19."
The diagnosis sent several MPs into isolation, including Health Minister Brad Hazzard, who later tested negative.
Parliament House workers were told to stay home on Thursday while a skeleton staff of MPs underwent rapid testing to allow the NSW budget to be passed.
Opposition Leader Chris Minns postponed his budget reply speech due on Thursday.
"All sides agree now is not the time for politics ... we need to get through what is a very difficult health situation in Sydney," he told Sydney radio 2GB.
Lower house Speaker Jonothan O'Dea on Thursday afternoon said no further MPs had tested positive, but some were still awaiting results.
A Nationals budget dinner attended by Mr Marshall before he knew he was infectious on Tuesday night potentially exposed dozens of MPs to the virus.
Ms Berejiklian said she'd given a speech at the event but had "zero contact" with Mr Marshall and had been deemed a casual contact.
Police also confirmed they were carrying out checks to ensure people were doing the right thing, issuing about 150 cautions to people for not wearing masks on public transport and other places.
Police also warned that during school holidays highway patrol would be checking people weren't breaking orders not to travel outside of Sydney.
A ban remains in place for non-essential travel outside of Sydney for people living or working in seven council areas that have been declared hotspots.
Masks are mandatory on public transport, at all indoor venues apart from homes and homes have a five person limit on visitors.
© AAP 2021