New South Wales to remain in lockdown a further four weeks, 177 COVID-19 cases overnight

New South Wales will stay in lockdown for a further four weeks as the state recorded 177 community cases of COVID-19 in the last 24 hours.

Premier Gladys Berejiklian said on Wednesday it was "fairly obvious" the way the case numbers had been climbing that the state would not be exiting lockdown as scheduled.

As a result, the state will remain locked down until at least August 28.

Of the 177 new cases recorded in the last 24 hours, 46 were infectious in the community, a number Berejiklian says is crucial to try and reduce.

"That's the key number we're really looking at - we really want that as close to zero as possible because that gives us confidence there aren't chains of transmission in the community."

She thanked the 94,000 people who got tested for the virus in the last day and reminded people to stay local to their homes while doing their critical shopping.

"We don't want shopping outside their local areas - locals stay local."

Although the lockdown will continue until late August, Berejiklian says year 12 students will be able to return to school on August 16, as they will be able to get the Pfizer vaccine. 

Rapid antigen testing will be introduced and doses of the vaccine will be diverted from regional NSW to Sydney to ensure students can be immunised.