Businesses and workers in NSW are "devastated" that the widespread lockdown will be extended by a week in a bid to crush the latest COVID outbreak.

Sydney's hospitality, entertainment and travel businesses are "devastated" by the extension of lockdown by an extra week, as they seek more financial support.

Pubs, restaurants, gyms, nightclubs, and other venues will remain closed in Greater Sydney, including Wollongong, Shellharbour and the Central Coast, until at least July 16, NSW Premier Gladys Berejiklian announced on Wednesday.

The five million plus people living in those areas have been told to stay home for a third week, unless it's necessary to leave.

Australian Hotels Association NSW CEO John Whelan said the sector needed more certainty and support.

"The lockdown extension is devastating news for more than 50,000 Greater Sydney-based staff who are out of work for another week, as well as the broader NSW hotel industry which has operated under restricted trading conditions for more than 15 months and counting," Mr Whelan said in a statement.

"Our staff have rent and bills to pay. Many are not eligible for government support and a third week with no work really hits hard."

Tourism Accommodation Australia CEO Michael Johnson said the occupancy rates of hotels in Sydney were less than two per cent, while their owners have to continue to pay bills.

"This is another blow to an already dire situation," Mr Johnson said.

"Hotels are losing millions of dollars each week and have little support to keep paying the bills and to keep paying staff."

NSW Treasurer Dominic Perrottet last week announced that small businesses who suffered during the lockdown would be eligible for grants of up to $10,000.

Ms Berejiklian on Wednesday refused to say whether that assistance would be ramped up in light of the longer lockdown.

"There's always opportunities for us to consider what more we can do," she said.

"I know and appreciate how difficult it is and the NSW government has already contributed billions towards our economy over and above what we anticipated to support everybody during COVID, whether it is various measures, direct grants or our measures we have undertaken."

She flagged that Mr Perrottet had been in contact with his federal counterpart Josh Frydenberg over the issue and they were "considering all those options".

However, Mr Frydenberg earlier indicated affected workers would not be getting any more support.

"Not at this stage," he told the Seven Network.

"There are two payments, the $500 and $325 payment, depending on the number of hours a week that have been lost for a person who has been subject to these lockdowns that have gone for longer than a week."

Meanwhile, the NSW government has been criticised for extending the lockdown beyond Sydney, despite no cases being recorded in some parts of the state.

Kiama MP Gareth Ward, who sits on the crossbench after quitting the government earlier this year, said there was no evidence to support the lockdown continuing in the Wollongong and Shellharbour local government areas.

"It makes no sense to limit individual liberty, damage business and cause hardship for families when there is no overriding and greater public health reason for doing so," he said in a statement.

Mr Whelan also criticised the persistent restriction in regional NSW, where masks are mandatory and there are limits on the number of people allowed in venues.