JBS is also Australia's largest meat and food processing company, with 47 abattoirs, feedlots and meat processing sites across the country, including Scone in the Upper Hunter.

But not a single one of its killing floors was operating nationwide on Tuesday after a cyber attack targeted the global food company, which services 100 countries across six continents.

Australian staff learned of the attack when they were turned away from their workplaces on Monday.

The company's US beef division, which includes operations in Australia, has issued a statement confirming the attack affected some servers supporting its North American and Australian IT systems.

"The company's back-up servers were not affected, and it is actively working with an incident response firm to restore its systems as soon as possible," it said.

"The company is not aware of any evidence at this time that any customer, supplier or employee data has been compromised or misused."

The company has warned a resolution will "take time" and may affect some customers and suppliers.

There was no mention of the country's extensive operations in South America.

Agricultural journalist Jon Condon, from Beef Central, has spent 40 years reporting on Australia's livestock industries and says early talk of food security issues is alarmist.

"We're just coming out of a drought so the cattle numbers being slaughtered are very low. There's enormous amounts of unused processing capacity in Australia at the moment," he told AAP.

He said the most pressing immediate issue is lost wages for workers, with abattoirs typically relying heavily on casual workers who show up each day looking for shifts.

"At this point JBS is not killing in Australia again today, anywhere, the same as yesterday," he said.

JBS exports about 70 per cent of what it produces in Australia and Mr Condon believes effects on supply should be minimal if the situation is resolved quickly.

"But of course the longer this goes on, the more serious it gets."

On Monday, federal Agriculture Minister David Littleproud said Australian agencies were working with their overseas counterparts to determine who launched the attack.

He says IT systems crucial for quality control in Australia were among those that had been affected.

"We need to make sure we can get that up and going to give confidence not just to consumers in Australia, but also to our export markets," he told ABC radio.

"They are obviously working with law enforcement agencies here in Australia and we're working in partnership with other countries to get to the bottom of this.

"Since it is a global attack it's important not to speculate that it's emanated from any particular place, just yet."

EARLIER: Australian authorities are part of an international hunt for cyber criminals who've shut down the nation's largest meat and food processing company, JBS Foods.

Agriculture Minister David Littleproud says the federal government is doing all it can to get Australian abattoirs functioning again, and to limit effects on domestic supply and export markets.

The company has 47 facilities across Australia, including abattoirs and feed lots, with one site located in Scone in the Upper Hunter. JBS facilities in other countries have also been hit in a cyber attack that could affect meat supply chains world wide.

Mr Littleproud says it's too soon to say who might be behind the attack which shut down computer systems including those that deal with quality control.

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"The technology they use goes to the heart of the quality assurance of the beef they are processing. We need to make sure we can get that up and going to give confidence not just to consumers in Australia, but also to our export markets," he told ABC radio.

"They are obviously working with law enforcement agencies here in Australia and we're working in partnership with other countries to get to the bottom of this.

"Since it is a global attack it's important not to speculate that it's emanated from any particular place, just yet."

He could not say if it was a denial of service attack or a ransomware attack, but warned that if it was not resolved quickly the economic consequences could be very serious.

"It will depend how long this goes on for, and how long JBS are offline, for it is a supply chain that starts from the farm gate, right through to feed lots, to truck drivers."

The Australian Meat Industry Employees Union has said thousands of workers could not do their jobs on Monday.

Australian Associated Press