The news prompted South West Coast MP Roma Britnell to call on Victorian Premier Daniel Andrews to act quickly and respond appropriately now that there was no need for a hard border with SA.

"It's disappointing they're throwing the cross border communities into chaos for no reason," she said.

"It's absolutely absurd"

Ms Britnell said weary border families and business did not need this chaos when the cluster is 500km from the border.

She said that as it stands now people in Nelson couldn't go grocery shopping Mt Gambier and get home tomorrow because of the border issue.

The Victorian Government introduced a 48-hour border closure with South Australia in response it its lockdown from midnight Thursday and a permit system would be introduced from midnight Saturday.

Police Commissioner Grant Stevens said the person claimed they had purchased a pizza from the pizza shop but they were working there for several shifts.

"Had this person been truthful to the contract tracing team we would not have gone into a six-day lockdown," he said

During the press conference on Friday, residents were told they were allowed to exercise with people in their own households, effectively immediately,

Premier Steven Marshall said a close contact linked to a pizza bar deliberately mislead the contact tracing team. "We now know that they lied," he said.

"I will not let the disgraceful conduct of a single individual to keep SA in these circuit-breaker conditions one day longer than what is necessary.

"Just as we have acted immediately to keep South Australians safe, we're going to lift them much sooner than previously advised,"

The Premier said he had promised not to hesitate to act on expert advice, and the advice was clear - a circuit-breaker was needed.

Mr Marshall said it was still a dangerous cluster and they now needed to find and isolate a new group of people.

As of midnight on Saturday, the stay at home order would repealed, he said. They would be replaced by new set of restrictions.

"To say that I am fuming about the actions of this individual is an absolute understatement. The selfish actions of this individual has put our whole state in a very difficult situation," he said.

Police commissioner Stevens said South Australia was still planning to relax border restrictions with Victoria on December 1.

Chief health officer Professor Nicola Spurrier said there were three new cases overnight and they expected that number to rise over the next few days.

She said all of those were already in quarantine and were close contacts of one of the medi-hotel security guards and aged-care home.

There were now 25 cases linked to the cluster, and more than 4500 close contacts would remain in quarantine despite the lockdown ending early.

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