New Zealand's Prime Minister Jacinda Ardern has joked that her partner's marriage proposal was an intimate moment with just the two of them, a police protection officer, a couple of locals and a dog that tried to eat chocolate her partner had brought with him.

Ardern spoke publicly for the first time Monday about her engagement to her longtime partner Clarke Gayford over the Easter break in the town of Mahia. She says she was surprised by the question and they've yet to make any wedding plans.

Reporters on Friday noticed Ardern wearing a ring on her middle finger and her office later confirmed the engagement.

Ardern says the ring belonged to Gayford's grandmother and doesn't fit on her ring finger.