Opposition leader Jodi McKay called on NSW Premier Gladys Berejiklian to press for a full lockdown at Friday's National Cabinet crisis meeting.

"If National Cabinet does not decide to put this country into lockdown, the Premier must go it alone," Ms McKay said.

"Everyone must go home and stay home."

Mr Barr put his support behind a full lockdown in order to save lives, after NSW Health revealed there were nine confirmed cases of COVID-19 in the Cessnock local government area by 8pm Wednesday (a figure that rose to 14 within 24 hours).

"This is not only about containment but slowing the spread so our health services can handle the number of cases coming in," Mr Barr said.

"With this rate of increase it could mean in the next 10 days there could be 90 people, we need to self-isolate now. There are people's lives at risk.

"Everyone needs to take responsibility. If you do not need to go out, stay at home. This will help slow the spread of the virus.

"Now is the time to take serious steps to protect you and your family.

"Given the measures to slow the spread of coronavirus (COVID-19), I have made the decision to close my electorate office to the public.

"I need to ensure I am looking after my staff and we are doing our bit to minimise the spread of COVID-19."

Mr Barr's office is still available by phoning 4991 1466 or emailing cessnock@parliament.nsw.gov.au.