Australia is set to strengthen food labelling laws after a series of hepatitis A infections were linked to frozen berries from China, Prime Minister Tony Abbott said Thursday.

Nanna's and Creative Gourmet brand raspberries and mixed berries were recalled after being linked to some 19 hepatitis A cases across the country this month, with poor hygiene or contaminated water at their packing factory thought to be responsible.

"With imported food in particular, people want to know more about where their food, where their products, are coming from," Abbott said, after pressure from consumer groups and farmers to make the process more transparent.

"We want to do this in a way which is as cost effective as possible. We don't want to add needlessly to the burdens of business but we also do want to ensure that consumers get the information that they need and the public is protected."

Abbott said his agriculture and industry ministers would submit a proposal to cabinet by late March on how new country-of-origin labelling would work.

The proposals include a graphic on packaging that includes the words "this product is made in Australia from", displaying the percentage that comes from Australia, Industry Minister Ian Macfarlane said.

Currently, products from local and imported ingredients do not give a breakdown of how much comes from each country.

The recalled products were packed in China and contained raspberries, strawberries and blackberries grown there, and blueberries from Chile.

Hepatitis A is a viral disease that affects the liver, causing abdominal pain, nausea, vomiting, fatigue and jaundice. It has an incubation period of up to 50 days.

The announcement came as a food scare involving tuna reportedly imported from Thailand hit a central Sydney cafe with four people suspected to be suffering scombroid fish poisoning after eating at the outlet.

Symptoms include severe headache, rapid heartbeat, stomach cramps, nausea, abdominal pain and sometimes diarrhoea.

Officials said the fish may not have been properly stored, with the New South Wales state food authority investigating.

Separately from the government, national MP Bob Katter and senator Nick Xenophon on Thursday introduced legislation for new food labelling rules that would include warnings on products not grown or processed in the country.

Australian Competition and Consumer Commission chief Rob Sims told reporters he would "strongly support anything that gives more transparency so that consumers have a better idea what they're buying".