Victorian Premier Daniel Andrews is confident his state’s tough COVID lockdown won’t lead to food shortages after crisis talks to help resolve the worst fears of some big industries.

“I wouldn’t want anyone to think there’s going to be empty shelves,” Mr Andrews said on Thursday.

“We will do everything we possibly can, not just the government but our public health team, compliance team, supermarkets, butchers, bakers, people who are stacking shelves. Everyone will do their utmost, their absolute best, to make sure what you need is on the shelf.”

Victoria reported 471 more virus infections on Thursday, well below Wednesday’s bleak record tally of 725. But its death toll rose by eight more to 170.

In NSW, there were 12 more coronavirus cases on Thursday – all from community transmission.

Supermarkets have been swift to reimpose purchase limits. Photo: AAP

Melbourne began a strict Stage 4 shutdown on Thursday to try to bring Victoria’s deadly COVID outbreak under control. There are also Stage 3 restrictions in regional Victoria.

There have also been last-minute amendments to strict orders for business after the federal government and industry groups said they feared the enforced reduction in warehouse and distribution capacity might hinder supplies of food across Australia.

In a deal thrashed out in crisis talks between the Andrews government and business leaders late into Wednesday and early on Thursday,  supermarket distribution centres and medical warehouses will have an extra two days to comply with restrictions.

But, from midnight on Sunday, they will have to reduce their capacity by a third to comply with the Victorian restrictions.

National cabinet will also discuss the potential shortages on Friday.

Mr Andrews was adamant he had struck a delicate balance as the six-week shutdown began.

“A lot of work has gone into driving down staff levels but, at the same time, protecting the amount of product that will be on supermarket shelves,” he said in Melbourne.

“That’s our aim. That’s what we think we can confidently deliver.”

Under other deals, red meat processors will switch to 66 per cent of capacity, although abattoirs with 25 or fewer staff will be exempt.

Poultry will fall to 80 per cent capacity because much less would have meant many birds were destroyed but not processed. That would have sparked significant chicken shortages.

Shopper are being urged to avoid a repeat of the panic buying of the early days of the pandemic.

There have already been reports this week of empty shelves at supermarkets across Melbourne, and a return to panic buying. Retailers have imposed purchase limits as a result.

“There’s no need for people to be trying to stockpile months and months of food,” Mr Andrews said.

“You may not necessarily be able to get exactly the cut of meat that you want but you will get what you need and you will get all the products that are, basically, fundamentally important to you. They will be there.”

Federal Industry Minister Karen Andrews said industry groups had not been “crying wolf” with concerns about supply chains.

But she doesn’t believe there will be food shortages.

“As long as people are sensible, buying what they need … I’m not envisaging that there’s going to be major problems,” she told ABC radio.

Elsewhere, Prime Minister Scott Morrison said Victoria’s tough six-week rules could cost the Australian economy up to $10 billion.

Mr Morrison said preliminary estimates from Treasury suggested the measures would shrink real gross domestic product by $7 billion-$9 billion in the September quarter.

Victoria’s new shutdowns are expected to put up to 400,000 people out of jobs.

As a result, headline unemployment is also forecast to peak at close to 10 per cent. But the real unemployment rate, which includes those not looking for work and those on zero hours, is tipped to be closer to 13 per cent.

“It is estimated – the increase in effective unemployment – to be between 250,000 and 400,000,” Mr Morrison said.

Just two weeks ago, and prior to Victoria ramping up its restrictions, Treasury had forecast the national jobless rate to peak at 9.25 per cent in 2020.

Mr Morrison said the latest forecasts were a “heavy blow” but not unexpected.

He also hinted that further stimulus could be forthcoming before the October 6 federal budget.

“The Treasurer and I are considering some further issues around JobKeeper,” he said.

“We are making announcements constantly. The budget will be in October and that will be another significant, arguably the most significant, instalment in these announcements.”

-with AAP