COVID-19: Sydney's Northern Beaches braces for lockdown as cluster grows

Sydney residents are bracing for another lockdown as their 'Northern Beaches cluster' cases continue to surge.

New South Wales Premier Gladys Berejiklian confirmed 23 coronavirus cases on Saturday, including 10 that were reported Friday.

Two other cases remain under investigation.

The Northern Beaches area is bracing for another lockdown from 5pm (local time) on Saturday to midnight on Wednesday.

Those living between the Sydney suburbs of Spit Bridge and Palm Beach are urged to stay at home where possible.

Premier Berejiklian says it is "likely" the state will see a repeat of those numbers in the next few days.

"We're asking you not to undertake non-essential travel, we're asking you not to undertake non-essential activity."

"We want people to essentially stay at home tonight and the next few nights so that we can ensure the virus doesn't spread."

There were 12,374 tests reported in NSW on Friday night, compared with 7,531 in the previous 24 hours.