NSW Premier Gladys Berejiklian confirmed on Friday morning NSW had recorded 28 cases in the last two days, 10 of those in the past 24 hours.

All but one is confirmed to be linked to the Northern Beaches cluster.

"If we get on top of this in the next two or three days all of us will be able to have a much better Christmas," she said.

"But if we don't get on top of it in the next few days, it could mean further restrictions down the track, we don't want to go to that."

Ms Berejiklian said a couple of cases did not live in the Northern Beaches region, so there might have been seeding into other areas.

She urged everyone in greater Sydney to be "extra COVID-safe".

IN OTHER NEWS:

Early Friday morning, the Victorian Department of Health and Human Services advised people already in Victoria who had visited the Northern Beaches region or other NSW exposure sites on or since Friday, December 11, should get tested and quarantine in their home or accommodation for 14 days from the date they left.

Anyone who was in the Northern Beaches region or other NSW exposure sites on or since Friday 11 December 2020 and arrives in Victoria after midnight Thursday 17 December 2020, must get tested and quarantine in their home or accommodation for 14 days from the date they left the Northern Beaches.

"The Victorian government will announce further advice for travellers arriving into Victoria from the Northern Beaches or other NSW exposure sites after midnight Saturday, December 19, 2020 later today," the department said just before 1am.

"The Victorian Department of Health and Human Services is working closely with NSW Health to ensure any people who have visited the high risk locations in NSW immediately get tested and self isolate."

The DHHS will be conducting spot checks on flights arriving from Sydney to remind passengers that anyone who has visited the Northern Beaches or the other exposure sites must get tested immediately and self isolate.

People who think they may have been exposed or have been to these locations is asked to contact the department on 1800 675 398.

"We will ensure that anyone who has been exposed to this outbreak - regardless of whether you normally live in Victoria, NSW or elsewhere - is supported to safely and appropriately self isolate and get tested," the department said.

Anyone from NSW who is in Victoria and who has even the slightest symptoms is urged to get tested immediately. There are almost 200 sites to get tested across Victoria; these tests are free for everyone and you will have your results by the next day.

Information about Covid-19 testing locations in Victoria is available at https://www.dhhs.vic.gov.au/where-get-tested-covid-19

Anyone who has recently arrived in Victoria from NSW can access the exposure sites here: https://www.health.nsw.gov.au/Infectious/covid-19/Pages/case-locations-and-alerts.aspx

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