Masked Mother's Day weekend in NSW

The restrictions - which extend to the Blue Mountains, the Central Coast and the Illawarra - will remain in place until at least the end of the weekend. They include compulsory masks on public transport and a 20-person cap on indoor gatherings.

But Premier Gladys Berejiklian doesn't want the curbs to suppress Sydneysiders' spirits, encouraging residents to keep their Mother's Day bookings for Sunday and continue supporting local businesses.

Liquor and Gaming NSW is urging businesses to do the right thing over the weekend too.

Compliance officers will be out in force across the state, checking venues are COVID-safe.

Businesses can be fined up to $5000 and forced to shut their doors for defying COVID rules, including the requirement all patrons check in.

"Now is not the time to get complacent, the COVID safety requirements are in place for a reason, and all venues need to make sure they are fully compliant," director of compliance Dimitri Argeres said.

Officers will also be checking those participating in the NSW government's Dine & Discover voucher program are complying with its rules.

"This includes not artificially inflating prices or allowing customers to use the vouchers to buy restricted products," Mr Argeres said.

NSW again diagnosed no new locally transmitted cases from more than 22,000 tests in the 24 hours to 8pm on Friday but authorities issued an alert for customers who visited Double Bay Woolworths.

Anyone who attended the store between 10.45am and 11.00am on May 3 must get tested immediately and isolate until a negative result is received.

The restrictions came after a man in his 50s from Sydney's east was diagnosed with the virus on Wednesday, followed shortly by his wife.

The man's strain has been linked to a man in hotel quarantine but health officials are yet to identify how it was passed between them.

Six new cases were diagnosed in hotel quarantine on Friday.

Australian Associated Press