Another month for Greater Sydney lockdown

More businesses will receive support, some tradespeople can re-enter customers' homes and year 12 students in hotspot areas will be vaccinated as a priority under the new measures.

But nearly five weeks of lockdown already endured by nearly six million people in Greater Sydney, the Central Coast, the Blue Mountains, Wollongong and Shellharbour hasn't been enough stop 1050 new infections in the past week.

"Delta is different," Premier Gladys Berejiklian said on Wednesday.

"I am as upset and frustrated as all of you that we were not able to get the case numbers we would have liked at this point in time but that is the reality."

The main drivers of transmission remained interactions in workplaces and households, often creating cycles of infection, Chief Health Officer Kerry Chant said.

"But on a positive note ... we know lockdowns work and we have to hold our course," Dr Chant said, stressing vaccination was a path out.

Three-in-ten NSW residents have received their first dose of either Pfizer or AstraZeneca, with one-in-eight having two doses.

The state's vaccination capacity exceeds 600,000 shots a week, according to state and federal sources.

The longer lockdown will allow more people to get vaccinated, particularly in eight local government areas where the virus is spreading quickest and walk-in AstraZeneca clinics are being rolled out.

Those areas - home to more people than Perth - now include the cities of Parramatta, Campbelltown and Georges River, meaning only authorised workers can leave.

Year 12 classes will resume citywide on August 16, with students in the eight hotspots to receive Pfizer jabs as soon as possible.

Those jabs will come from supplies bound for the bush, after other states declined to part with their supplies.

"People would appreciate the stress year 12 students are going through," Ms Berejiklian said.

Similar to a measure from Victoria's extended lockdown, a singles bubble will allow one designated family member or friend to visit a person living alone.

From midnight, residents will be banned from entering shops more than 10 kilometres from their home, unless it's in their council area.

From Saturday, construction in non-occupied settings can resume outside the eight hotspots, subject to social distancing.

But with two-in-five construction workers living in hotspots, Urban Development Institute of Australia wants fully vaccinated workers permitted back on site.

Tradespeople, including in-home cleaners, living and working outside the hotspots will be permitted into clients' homes, provided there is zero contact with residents.

"If you're getting an air-conditioner replaced for a couple of hours and you have an opportunity to do your groceries, we'd encourage that," Deputy Premier John Barilaro said.

The state and federal government JobSaver program was significantly boosted, opening support to struggling businesses with a normal annual turnover of $50 million to $250 million.

Businesses that maintain their employee headcount will now be eligible for up to $100,000 per week, up from $10,000, based on 40 per cent of their weekly NSW payroll.

The federal government increased weekly support payments for individuals, with full-time workers to receive up to $750 and some job seekers who've lost work eligible for $515.

Government support now exceeded $650 million per week.

NSW Opposition Leader Chris Minns supported the lockdown but called for the release of modelling showing the new restrictions will bring cases to close to zero by August 28.

At least 68 of the 177 people diagnosed with the virus on Tuesday were circulating in the community for all or part of their infectious period. The isolation status of another 62 remains unknown.

A woman in her 90s became the 11th death of the current outbreak. 56 people are in intensive care, including two teenagers and five in their 20s. Twenty-two patients are on ventilators.

Australian Associated Press