New Zealand Prime Minister Jacinda Ardern has tested positive for coronavirus.

She has been in isolation since May 8 after her fiance Clarke Gayford contracted the virus. Their daughter Neve, 3, tested positive on Wednesday, she said in an Instagram post on Saturday.

Ardern will miss what is arguably her government’s biggest week in parliament, with its emissions reduction plan due to be unveiled on Monday and budget to be released on Thursday.

“This is a milestone week for the government and I’m gutted I can’t be there for it,” Ardern said.

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“Our emissions reduction plan sets the path to achieve our carbon zero goal and the budget addresses the long-term future and security of New Zealand’s health system.

“But as I said earlier in the week isolating with COVID-19 is a very Kiwi experience this year and my family is no different.”

Ardern is due to give Harvard University’s Commencement speech on May 26.

Ardern said at this stage her travel arrangements to the US were unaffected.

New Zealand’s COVID-19 rules mean Ardern must isolate at home until May 21.