Ardern was earlier granted the title – the highest honour given to a New Zealander, with only 20 living people being accepted as members into the order at any time – last year in the King’s Birthday Honours.

However, she said travel commitments had meant she hadn’t been able to make it to an investiture ceremony on home soil.

“Being away from home means I haven’t been able to take part in one yet,” she said of the ceremony.

“It looked like that would be the case again this year, when in the margins of an Earthshot meeting the possibility of having the ceremony in the UK was raised with me.”

Having been “lucky” to get to know and work with Prince William over the years, she accepted the Windsor Castle investiture and will also have her family with her, she said.

“But I knew there would be pieces of home I would miss. I am so humbled and thankful that Whaea Esther from Ngāti Ranana will not only join me, but is allowing me to once again share in one of Ngāti Ranana’s Kākahu for the ceremony,” Ardern said.

“It will be a really special day – but amongst it all, it will be home that I will be thinking of.”

As New Zealand’s 40th Prime Minister, she served from October 2017 to January 2023.

She came to power in a coalition government before, three years later, Labour was able to form a majority government on its own after winning 50% of the vote.

She led the country through the Covid pandemic and the horrific Christchurch mosque attacks and has been taking part in global initiatives to tackle climate change and support emerging leaders.

Prince William will be overseeing the ceremony after his wife Princess Kate recently made her first public engagements since completing her cancer treatment.

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