Metropolitan Melbourne and a small section of regional Victoria is being placed into lockdown for six weeks.
As of 11.59pm on Wednesday people who live in the city and greater suburbs of Melbourne, as well as those in the Mitchell Shire (north of Melbourne), will be placed back under stage three restrictions.
Stage three restrictions are the same as what was imposed at the height of the lockdown.
People living in this area will only be able to leave their homes to shop for food and supplies, to receive or provide care, to exercise, and to study or work if they can't do so from home.
Premier Daniel Andrews made the announcement after the state recorded its biggest COVID-19 spike since the pandemic began.
There were 191 new cases confirmed on Tuesday, following 127 on Monday.
The majority of the cases remain in the inner-north and west of Melbourne.
Except for Mitchell Shire, regional Victoria is excluded from the lockdown.
Mr Andrews said the move was designed to keep regional Victoria safe to prevent further spread of the virus.
"Regional Victoria has very few cases, and vast parts have no cases," he said.
"This is designed to keep it that way."
In Melbourne, visitors will no longer be welcome at homes and people cannot gather in groups of more than two.
Funerals will return to 10 mourners while only be five people can attend a wedding.
Schools in affected areas will not open their doors for term three, which was due to begin on Monday, with students set to return to distance learning, except for senior secondary students and special schools.
School holidays will be extended by a week to give teachers time to prepare.
Victoria recorded its highest number of new cases in the state since the start of the pandemic on Tuesday, following an increase of 127 cases on Monday, which was also a record.
"These are unsustainably high numbers of new cases," Mr Andrews said.
"We have to be realistic about the circumstances that we confront.
"We have to be clear with each other that this is not over and pretending that it is because we all want it to be over is not the answer. It is indeed part of the problem."
