The NSW government has announced a $1 billion support package for businesses hit hard by the Omicron outbreak as the state records its deadliest day of the pandemic so far.

There were 52 deaths and 13,524 new positive COVID-19 tests reported in the 24 hours to 8pm on Saturday.

NSW Premier Dominic Perrottet said the government had the back of every business and worker in the state.

"No other jurisdiction, no other state to date has provided financial support except NSW," Mr Perrottet told reporters on Sunday.

The package includes a payment of up to $5000 per week, or 20 per cent of payroll, for businesses with a turnover between $75,000 and $50 million who suffered a 40 per cent downturn in January, and project to do the same in February.

NSW Treasurer Matt Kean said the support package will help businesses "get through to the other side".

"When we get out of this wave we expect a snapback and that the economy will bounce back better on the other side of this," Mr Kean said.

He was however "disappointed" the package was funded by the state as he was hoping to make the announcement alongside the prime minister and federal treasurer, but they weren't "to be found".

"Rather than the commonwealth government stepping aside we expect them to step up as well," he said.

Federal Finance Minister Simon Birmingham said the NSW package was in addition to $63 billion in assistance already provided to the state by the Morrison government.

"We welcome states and territories putting in their bit on top of the billions of federal support that we have provided," he told reporters on Sunday.

The government has extended the Small Business Fees and Charges rebate program to $3000, which can include 50 per cent of the costs incurred to get rapid antigen tests for the workplace.

Relief for commercial landlords has also been extended until March 13.

Opposition treasury spokesman Daniel Mookhey says the support is too little, too late and "there is no recognition for the incredibly tough six weeks businesses have already been through".

"Businesses need to prove they lost 40 per cent of their trade in January, and yet they won't be compensated for that January loss."

"It's concerning that the support available to businesses will be half that of last year, despite the impacts on many businesses being worse than last year," Mr Mookhey says.

Opposition small business spokesman Steve Kamper says the government's refusal to backdate payments is "a cruel trick on businesses who have been hanging out for support".

Daniel Hunter, the CEO of advocacy body Business NSW, said the package would help keep the doors open for many businesses.

"What's crucial now is that customers have the confidence to return to businesses and do their shopping in a safe manner," he said.

Westpac chief executive of consumer and business banking Chris de Bruin says the bank's customers in retail, hospitality and entertainment sectors have been hit hard as consumers "take a more cautious approach to living with the virus".

Australian Industry Group chief executive Innes Willox also had concerns about "the self imposed lockdown by many in the community".

"The dollars need to be matched by a concerted effort by governments to start putting the pandemic behind us both through words and deeds," Mr Willox said.

He says health authorities should stop reporting daily virus statistics because the "increasingly unreliable" data makes the community uneasy about returning to normal life.

There are currently 2663 people hospitalised with the virus, 182 of whom are in intensive care, with 73 people on ventilators.

Chief Health Officer Dr Kerry Chant said 31 of the 52 deaths reported on Sunday were in aged care facilities.