Venice: The World Health Organisation says it is working with authorities in Hong Kong to understand how a pet dog tested positive for coronavirus, after upgrading the global risk of the COVID-19 outbreak from "high" to "very high".

Hong Kong officials revealed nasal and oral samples taken from the animal, which belongs to a 60-year-old infected woman, had returned a "weak positive" but said there was still no evidence that pets can contract COVID-19 or infect humans.

In a statement, the Agriculture, Fisheries and Conservation Department said it had quarantined the dog and would conduct more monitoring and testing to confirm whether it had "really been infected with the virus or this is a result of environmental contamination of the dog's mouth and nose".

Hong Kong said it "strongly advised" that pets of citizens infected with coronavirus be handed over to the government for quarantine and surveillance for 14 days.