A request has been sent to carry out whole genome sequencing for the case which is expected to determine whether the Covid case is from the Omicron variant.
A result is expected on Sunday, according to the statement.
The flight in question “has been added to the Ministry of Health website as a location of interest this evening,” it said.
The statement added that Ms Ardern is asymptomatic and is feeling well.
She will be tested “immediately” again on Sunday.
Other government officials, including the governor-general and members of her staff, were also on board the flight and will follow the same self-isolation measures.
“All other passengers on board NZ8273 are also deemed close contacts and are required to self-isolate, get tested immediately and remain in isolation for 10 days following their exposure,” the statement said.
A dozen flights were listed as exposure events late Saturday by the country’s health officials, in an indication that one or more flight crew may have been infected, reported the Associated Press.
The prime minister and the governor-general were in the country’s Northland region to film a broadcast for Waitangi Day.
The national day marks the signing of the Treaty of Waitangi – known as the country’s founding document – that was signed on 6 February 1840.
Ms Ardern had nearly a week ago cancelled her wedding ceremony with fiancé Clarke Gayford due to the country’s new Covid restrictions.
“My wedding will not be going ahead,” she had said.
“I am no different to, dare I say it, thousands of other New Zealanders who have had much more devastating impacts felt by the pandemic, the most gutting of which is the inability to be with a loved one sometimes when they are gravely ill. That will far, far outstrip any sadness I experience.”
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