MELBOURNE - Australian officials on Sunday extended a strict virus lockdown of the country's second-biggest city by two weeks, saying new cases had not dropped enough to prevent another spike.

Melbourne residents were due to exit a harsh six-week lockdown next weekend but face continued restrictions for months to come, with Victoria state premier Daniel Andrews saying the current lockdown would remain in place until September 28.

"If we open up too fast then we have a very high likelihood that we are not really opening up at all -- we are just beginning a third wave," he told a press conference.

"And we will be back in and out of restrictions, coming in and out of lockdown, before the end of the year."

Just 63 new cases and five deaths were recorded in Victoria on Sunday, after peaking above 700 at the height of the outbreak, but health officials are taking a cautious approach.

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Hopes of a return to normality this month have been dashed, with an overnight curfew, restrictions on visitors to homes and a limit on travelling more than five kilometres (about three miles) set to remain in place until at least October 26.

Announcing the roadmap for the easing of restrictions, Andrews said that rushing to experience a "brief period of sunshine" would likely lead to the virus again spiraling out of control.

The toughest rules will be eased in Melbourne from September 13, with an overnight curfew beginning an hour later at 9:00 pm, daily exercise increased to two hours and small "social bubbles" created for people living alone.

Under the government's plan, childcare centers will reopen and up to five people will be able to gather outdoors from the end of September -- but only if cases fall below an average of 50 per day.

Rules for people living in regional and rural Victoria will be relaxed more quickly, due to small numbers of active cases in those areas.

The announcement comes a day after more than a dozen anti-lockdown protesters were arrested in Melbourne during clashes with police.

Hundreds attended the illegal gathering organised online by conspiracy theorists, labeling the government's response to the pandemic overblown or an outright "scam".

Australia has been relatively successful in containing the virus, with the country recording just over 26,000 cases and 753 deaths in a population of 25 million.

The vast majority were reported in Melbourne over the past two months, while other regions have rolled back restrictions after largely bringing the virus under control.

© Agence France-Presse