There is no significant evidence of coronavirus being spread through food trade and such reports "need to be minimised", Maximo Torero Cullen, chief economist of the United Nations food and agriculture agency, said on Wednesday.
The FAO has previously said it does not see food production in supplier countries as a source of the novel coronavirus, he told the Global Grain conference.
China has ramped up testing of frozen foods after saying it has repeatedly discovered the coronavirus on imported products and their packaging, triggering mass scale testing of food and related personnel, suspension of certain imports and disruptions to trade flows.
China, which has suspended imports from 99 suppliers in 20 countries, argues these measures are needed to prevent more arrivals of the virus in a country that has largely contained the epidemic domestically.
But major food-producing countries are growing increasingly frustrated with China's scrutiny of imported products and are calling on it to stop aggressive testing for the coronavirus, which some say is tantamount to a trade restriction.
China says it has found the virus on the packaging of products including German pork, Brazilian beef and Indian fish, but foreign officials say the lack of evidence produced by authorities means it is damaging trade and hurting the reputation of imported food without reason.
In a World Trade Organization (WTO) meeting on 5-6 November, Canada called China's testing of imported foods and rejection of products that had positive nucleic acid tests "unjustified trade restrictions" and urged it to stop it, said a Geneva-based trade official briefed on the meeting who declined to be identified.
Supported by Australia, Brazil, Mexico, the UK and the US, Canada argued that China had not provided scientific justification for the measures, said the official.
The pushback came after months of growing frustration at the way customs and health authorities have been increasingly scrutinising imports, which trade partners complain does not adhere to global norms.
"Whenever a health authority performs a test, and finds something, they should share the results," said a Beijing-based diplomat who declined to be identified as he was not authorised to speak to media.
"We haven't received one single lab analysis," he said. "Everyone is asking 'Is it true? Did they really find anything?' Everyone is surprised that no proof is given."
China began testing chilled and frozen food imports for the virus in June, after a cluster of infections among workers at a wholesale food market in the capital.
The World Health Organization says neither food nor packaging are known transmission routes for the virus.
But China, which has all-but stamped out local transmission of the disease, says there is risk of the virus re-entering the country on food products.
China has pointed to its isolation of live coronavirus from samples on imported frozen cod, a world-first, as proof, though with the evidence unpublished, that the coronavirus can be transmitted from food to people.
Speaking at a food safety conference this month, Gudrun Gallhoff, minister counsellor for health and food safety at the European Union delegation to China, said exporters needed more information on China's test methods and results.
"If you have trade partners you have to treat them fairly and give them a chance to be complicit," she said.
