"The demand has been pretty unprecedented, unlike anything we've seen before."

Customers attempting to buy toilet paper from Woolworths online have been told it is out of stock, while Amazon Prime customers have been told toilet paper deliveries will take a week or more rather than the traditional two days.

The rationing came a day after Prime Minister Scott Morrison intervened in the supply chain crisis, contacting the chief executives of Coles and Woolworths and asking for assurance that essential items would not run out.

The Prime Minister urged people not to panic, saying supplies were guaranteed.

Woolworths said the limit of four packs per customer transaction applied in-store and online and would help shore up stock levels as suppliers ramped up local production and deliveries in response to higher than usual demand.

"Our teams are continuing to work hard on restocking stores with long-life food and groceries from our distribution centres," a spokesman said.

"The vast majority of the products in our range remain available for our customers as normal."

While there were temporary gaps in supplies of pasta, flour and rice these products were being refilled overnight.


"We apologise to customers for the inconvenience caused by temporary stock shortages and thank them for their patience," he said.

Asked on Tuesday if Woolworths was considering imposing buying limits, Woolworths said only that it was working with suppliers to ramp up deliveries and production to help maintain stock availability.

Coles and Woolworths appear to have been caught by surprise by the panic buying, saying last week there had been no evidence of pantry-filling.

British supermarkets have drawn up “feed the nation” contingency plans to help cope with panic-buying brought on by the escalating coronavirus epidemic.

Australian supermarkets believe their supply chains are adequate to cope with the crisis.

"We're not concerned about long term supply issues, we wanted to make sure more people can access the products as we work through this patch and put a reasonable quantity limit on it," the Woolworths spokesman said.

Coles said it had comprehensive response plans across its network to cover contingencies, including resourcing and product sourcing.

"We consider this planning part of our core operating model," Coles said.

“We are working with our suppliers and transport partners to manage our response to the coronavirus and minimise any long-term impacts on product availability for customers," it said.