It's thought the Covid-19 outbreak may have begun in a Chinese market that sold wildlife alongside food.
The Australian government is calling for the G20 countries to take action on wildlife wet markets, calling them a "biosecurity and human health risk".
Australia is not yet calling for a ban - but says its own advisers believe they may need to be "phased out".
"Wet markets" are marketplaces that sell fresh food such as meat and fish.
But some also sell wildlife - and it's thought the coronavirus may have emerged at a wet market in Wuhan that sold live, "exotic" animals.
The Huanan market in Wuhan reportedly offered a range of animals including foxes, wolf cubs, civets, turtles, and snakes.
What did Australia say?
The Australian government called for an investigation into wildlife wet markets after a meeting of G20 agriculture ministers.
Speaking to the ABC on Thursday, agriculture minister David Littleproud said he was not targeting all food markets.
"A wet market, like the Sydney fish market, is perfectly safe," he said.
"But when you add wildlife, live wildlife, exotic wildlife - that opens up human risk and biosecurity risk to the extent we have seen.
"And in fact, China themselves reported this to the World Organisation for Animal Health, that that was the cause of Covid-19."
Mr Littleproud said he wanted to "get the science" first, but said: "Even our chief veterinary officer is telling us that he believes they [wildlife wet markets] may need to be phased out."
What is the risk of wildlife wet markets?
The exact origin of the new coronavirus is not known, but the evidence suggests it came from an animal.
According to the World Organisation for Animal Health, Covid-19 is a "close relative" of other viruses found in horseshoe bats.
So the virus could have passed from bat to human, or via an "intermediate host" - one theory is bat, to pangolin, to human.
The Sars coronavirus is thought to have emerged in bats before passing to civets and then humans. The Mers coronavirus passed from camels to humans, after probably emerging in bats.
What has China done so far?
In January, China issued a temporary ban in the trade in wild animals, as it did during the Sars outbreak.
A month later, the government "thoroughly banned the illegal trading of wildlife" and "eliminated the consumption of wild animals to safeguard people's lives and health".
But since then, a number of reports have said wildlife is still being sold in markets in China and elsewhere.
More recently, the head of the World Health Organization said all governments must "rigorously enforce bans on the sale and trade of wildlife for food".
WHO head Tedros Adhanom Ghebreyesus said: "When these markets are allowed to reopen, it should only be on the condition that they conform to stringent food safety and hygiene standards." BBC
Despite strengthened law enforcement to protect wildlife, legal loopholes are hindering Vietnam’s efforts, activists have said.
It is part of the campaign 'Don’t Consume Wildlife to Protect Your Health And Of the Community'.