Jacinda Ardern shows off the cake she made for Neve's first birthday

Prime Minister Jacinda Ardern has unveiled the cake she made for the first birthday of her daughter, Neve.

On Friday evening, Ardern posted on Instagram an image of the NZ Women's Weekly Kids' Party Cakes book, asking for luck before she tried to "magic up a passable cake for the big first birthday".

She's now revealed her creation with another post on Instagram showing a large bunny-rabbit cake covered in coconut.

"I may be smiling but about an hour earlier I was not enjoying the first birthday cake making experience (like just about every parent I know!)," she said in the post.

"I recommend cakes that you can legitimately cover in coconut - it hides almost everything."

Neve's birthday was on Friday and her father, Clarke Gayford, posted an image on Twitter showcasing a present received from Prince William - a Buzzy Bee.

Ardern announced her pregnancy on January 19 last year, via Instagram. She posted an image of three fish hooks, to represent her family.

Since Neve's birth, she's been the focus of fascination by local and world media. At three-months-old, Neve was photographed with her parents at the United Nations General Assembly.

Ardern was the world's second Prime Minister to give birth while in office. The first was Pakistan's late two-time Prime Minister Benazir Bhutto.

Neve was last spotted publicly earlier this month on June 6 at the Devonport naval base at a ceremony which marked the 75th anniversary of D-Day.