Professor Michael Baker, of the University of Otago, Wellington, said today that WHO officials are actively reconsidering the global health organisation's stance on face masks.
"It will almost certainly change," Prof Baker told the Otago Daily Times' Weekend Mix.
To date, WHO has said there is no evidence wearing a mask protects against the virus. It only recommends the use of masks by members of the public who have symptoms or are caring for people infected with Covid-19.
The ODT understands the WHO announcement is likely to be made next week.
New Zealand's Ministry of Health says for most people wearing masks is not recommended.
The Ministry has been asked whether a U-turn by WHO would see it changing its advice to New Zealanders. The Ministry has also been asked whether a change of policy would mean it was compulsory to wear face masks in public.
A response from the Ministry has not yet been received.
An unnamed source said the Ministry was likely to want to keep its advice aligned with that of WHO.
Prof Baker is in favour of face masks.
He said at Level 2 there was still the potential for the virus to be circulating in the country.
Face masks would also give people confidence to use public transport and would mean buses and other public transport could operate at full capacity, he said
"But the main reason is that we would then have masking as something we know.
"It is not yet second nature for us in the Western world," Prof Baker said.
"With better border controls and the use of masks we could have avoided the severe lockdown we had."