Ardern appeared unfazed by the drama, agreeing to continue the interview.
A 5.8 magnitude earthquake was felt as far north as Gisborne and near the bottom of the South Island, according to Geonet.
Newstalk ZB's Adam Cooper said it was a "very big quake".
"A rattler, went on for a long time," he said.
Geonet has revised the quake's depth to 37km, 30km northwest of Levin. Originally it said it was a 5.9 magnitude quake, and later revised that to 5.8.
It struck at 7.53am.
It was categorised as "strong".
More than 22,500 people had reported feeling the quake by 8am. Almost 100 said it felt "severe" while 10 said it felt "extreme."
On social media, many joked that the PM might be handling the latest in a series of disasters.
"Do you think Jacinda felt that and thought "you've got to be f***ing kidding me?" joked one user.
