Acting Victorian Premier Jacinta Allan told Victorians the state would close its border to all of NSW from 2 January because of an increase in case numbers in NSW, where 10 new cases were confirmed on Thursday.
"Obviously this is going to cause some disruption for Victorians who may be holidaying, we do apologise for this disruption, however as I said, these difficult decisions are about protecting our community," she said.
"It is a decision based on the public health advice.
"It is based on the numbers coming out of NSW and it is also based on wanting to make sure we lock in the precious gains and sacrifices Victorians have made."
The Acting Premier said there were thousands and "possibly tens of thousands" of Victorians in NSW who would need to get home.
"We have been sending a very strong message for the best part of a week-and-a-half, 10 days now, advising people to think very carefully about their travel to NSW," she said.
Allan said Victorian travellers in NSW who arrived back in their home state on Thursday would be required to have a Covid test and isolate at home until they had their results back.
Victorians who make it home on Friday will need to isolate in their homes for 14 days, while Allan said any Victorians returning from 2 January would be required to go through hotel quarantine for 14 days.
At the Garden of Eden Caravan Park, where 95 percent of guests were from Victoria, the press conference was watched live on devices by many campers.
Manager Allan Carlson said he was "really pissed off" that his community, just a 45-minute drive from the Victorian border, was included in the hard closure, even though the local region didn't have any coronavirus cases.
"We have a thousand people in their caravans and everyone was happy and now none of them are happy because they all have got to go home," he said, speaking to the ABC on Thursday after the announcement.