King Charles hosted South African president, Cyril Ramaphosa, at Buckingham Palace – and was supported by key members of his family, including the Prince and Princess of Wales.
WATCH: Princess Kate gets the giggles during King's speech
Mother-of-three Kate stunned onlookers in a bridal white Jenny Packham 'Elspeth' dress, which was adorned with sequins. She completed her show-stopping look with the Lover's Knot tiara – a favourite of the late Princess Diana.
And while Kate was the absolute epitome of style and sophistication, she did let her composure slip, momentarily, during the speech given by her father-in-law, King Charles.
The Princess looked incredible at the state banquet
The kind-hearted monarch chose to open his speech using six greetings from nine African languages – including Venda, President Ramaphosa's own language.
His efforts went down a storm with his VIP guest, who could be seen reacting with enthusiasm and turning to the Princess after each utterance.
President Ramaphosa was delighted by Charles's speech
His passionate response certainly made its mark on Kate. She could be seen giggling away as President Ramaphosa listened to Charles's greetings before leaning in to share a few words.
During his speech, the King touchingly reflected on his late mother's relationship with South Africa, saying: "The late Queen had the great pleasure of hosting Presidents Mandela, Mbeki and Zuma for State Visits to the United Kingdom, at all of which I was present.
The King included words in the President's own language
"On each of those occasions, she expressed her admiration for your country and its people, its vibrancy, natural beauty and diversity.
"And she always talked warmly of her return to your country in 1995, as the guest of President Mandela, after the momentous events – driven from within South Africa and supported by so many around the world, including here in the United Kingdom – that brought democracy to your country.
The King and President shared a toast
"During one of my own visits to South Africa, in 1997, President Mandela told me that he had conferred on my mother a special name – Motlalepula, meaning 'to come with rain'.
"I have been reassured that this was a mark of the particular affection President Mandela felt for the Queen... rather than a remark on the British habit of taking our weather with us!"
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