Victoria has recorded 1069 new COVID-19 infections and a further two virus-related deaths.
The state is now managing almost 11,400 active coronavirus cases. There are 310 COVID patients in Victorian hospitals, 74 of them in intensive care and 37 who require ventilation.
The total number of deaths in Victoria since the pandemic began stands at 1416.
Health officials say virus testers processed more than 67,300 results on Saturday.
Victoria is 92 per cent fully vaccinated for everyone aged 12 and over.
As of Saturday, authorities were responding to three existing Omicron infections.
"One of the positive cases is a returned traveller who was previously identified with the Omicron variant while in hotel quarantine," the health department said.
"The other two positive Omicron cases sat together in the same row on a flight that landed in Melbourne from Dubai on 30 November.
"A third person who also sat in the same row has tested positive for COVID-19 and genomic sequencing is under way to confirm the variant."
Testing was also being conducted in relation to four other passengers on the same flight and three household contacts.
On the advice of Chief Health Officer Brett Sutton, Premier Daniel Andrews made a formal pandemic declaration that will apply to the entire state from 11.59pm on Wednesday, when the current state of emergency expires.
It's the first since new public health laws came into effect.
Mr Andrews says he is satisfied COVID-19 continues to be a serious risk to public health throughout Victoria.
Professor Sutton believes the protective measures are also necessary to ensure the Victorian health system is not overwhelmed.
The state's Public Health and Wellbeing Amendment Act allows the premier to declare a pandemic and health minister to enforce orders such as lockdowns, mask-wearing, vaccination mandates and quarantine.
Sunday marks the seventh consecutive day Victoria has recorded more than 1000 virus cases.
Australian Associated Press
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