The Prince and Princess of Wales shared a personal message thanking Jacinda Ardern following the New Zealand prime minister's resignation announcement.
In a tweet on Tuesday night, Prince William and Kate wrote: "Thank you @jacindaardern for your friendship, leadership and support over the years, not least at the time of my grandmother’s death. Sending you, Clarke and Neve our best wishes. W & C."
WATCH: Prince William receives special greeting during first meeting with Jacinda Ardern
The then Duke of Cambridge met Jacinda for the first time publicly in April 2019 when he carried out a solo trip to New Zealand to pay his respects to the victims of the Christchurch mosque shootings.
And last July, William held an audience with Jacinda at Kensington Palace during her first visit to the UK since the pandemic began.
Prince William visited Christchurch following the attacks in 2019
The Prince also personally asked Jacinda to stand in for him at an environmental summit in New York, which took place just a couple of weeks after Queen Elizabeth II's death.
"I am an exceptionally poor substitute but I also know we all understand the need for His Royal Highness to be with his family at this time," she said in a speech at the time.
Jacinda was one of the hundreds of world leaders to attend the late Queen's state funeral at Westminster Abbey on 19 September 2022.
Jacinda attended Queen Elizabeth II's state funeral
The 42-year-old, who became the world's youngest female head of government at the age of 37 in 2017, announced her resignation in an unexpected announcement on 19 January.
"I'm leaving, because with such a privileged role comes responsibility – the responsibility to know when you are the right person to lead and also when you are not. I know what this job takes. And I know that I no longer have enough in the tank to do it justice. It’s that simple," Jacinda said.
Her term as prime minister will conclude no later than 7 February but she will continue as an MP until the election this year.
"I am human, politicians are human. We give all that we can for as long as we can. And then it's time. And for me, it's time,” she added.
Jacinda and her fiancé, Clarke Gayford, welcomed their first child, Neve, in June 2018.
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