At least 20,122,700 cases of coronavirus have been registered in 196 countries and territories. Of these, at least 12,080,900 are now considered recovered.
Daily infections in Victoria peaked at 725 on Aug. 5 and have been trending lower in recent days, following the imposition of a hard lockdown in Melbourne on July 19.
The city-state went into a lockdown in mid-April after mass outbreaks in cramped migrant worker dormitories pushed its caseload to one of the highest in Asia.
President Vladimir Putin said on Tuesday that Russia had become the first country in the world to grant regulatory approval to a COVID-19 vaccine after less than two months of human testing.
"This is something we have prepared for," Ardern said in a surprise news conference, adding that the increased caution was as the source of the virus was unknown.
He said that the tourism sector in Pakistan has been reopened but its continuity depends on the behavior of the people who should continue to take precautionary measures against the coronavirus.
New York, London and some other major cities currently have only a fraction of their normal workforce in offices as employers and governments have told staff to work from home where possible.