This, she says, gave her a "deep personal connection" to the country and an appreciation of the relationship between New Zealand and the UK.
She points out that this close relationship is ingrained in the history of New Zealand.
"After all, around four in every five New Zealanders still claims British heritage; our foundational Treaty of Waitangi of 1840 was signed by Māori chiefs and representatives of Queen Victoria, and our people served alongside one another through two world wars," Ardern says.
This, she argues, has also extended into more modern times, with the tradition of the OE (overseas experience), which sees many young Kiwis head to the UK to work and travel.
"At any stage, about 60,000 Kiwis are resident in the UK," she says.
She says that this free movement of people between New Zealand and the UK brought many benefits, including trade and investments.
Ardern would like to see this grow in the coming years.
The UK is currently New Zealand's fifth largest trading partner, and Ardern says there is potential to deepen this partnership further through a new free-trade agreement between the two countries
"[It] would go a long way towards unlocking this potential, enabling businesses in both countries to work more closely together to seize opportunities in the global economy," she says.
"New Zealand is ready to begin negotiations towards a bilateral free trade agreement when the UK is in a position to do so."
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