Former New Zealand Prime Minister Jacinda Ardern revealed on Friday that she is in the process of writing a book to be published worldwide discussing leadership rather than politics.

The former leader of the Pacific nation resigned earlier this year, stating that she no longer had "enough in the tank" to remain in her position.

Ardern posted on her Instagram page that she wanted her book to focus on how "you can be your own kind of leader and still make a difference".

"I didn’t want to write a book that hauled over the internal politics of the last five years, and then someone convinced me that I didn’t have to," she said. "It’s the kind of book that would have made a difference to my 14-year-old self."

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As the world’s youngest female head of government elected as prime minister in 2017 at age 37, she led New Zealand through attacks such as the two mosques in Christchurch, and disasters like the White Island volcanic eruption.

After five years serving as prime minister, she said that she did not want to write "a book that hauled over the internal politics," of her time in office.

The former leader is due to take up dual fellowships at Harvard University in the coming few months.