King Charles looks suave as he arrives at the Cartier Queen's Cup Polo - with Princess Diana's twin nieces Lady Amelia and Eliza Spencer among the glittering stars at event

King Charles cut a dashing figure as he arrived at the Cartier Queen’s Cup Polo on Sunday afternoon, where guests also including Princess Diana‘s twin nieces.

The monarch, 75, brought a regal touch to the final day of the prestigious tournament, which was held this year in Egham, Surrey.

Guests to the exclusive event also included Lady Amelia and Lady Eliza Spencer, 31, the twin daughters of Diana’s brother, Charles Spencer.

Sponsored by Cartier since 2012, the Cartier Queen’s Cup is one of the world’s leading polo tournaments and features some of the sport’s top players and ponies.

The tournament takes place over three weeks, with the first trophy presented by the King’s late mother, Queen Elizabeth II, in 1960.

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King Charles cut a dashing figure as he arrived at the Cartier Queen’s Cup Polo on Sunday

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The prestigious polo tournament takes place over three weeks, with the first trophy presented by the King’s late mother, Queen Elizabeth II , in 1960

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Charles’s appearance came just a day after the much-anticipated Trooping The Colour ceremony in London, where he was joined by the Princess of Wales for his official birthday

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Charles wore his favoured Moscot sunglasses coupled with a lightweight beige suit, a dapper navy, red and gold striped tie and brown suede shoes

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Royal blood: The nieces of Princess Diana, Lady Amelia Spencer and Lady Eliza Spencer, attended the Cartier Queen’s Polo in Egham on Sunday

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Lady Eliza Spencer wore a summery white short-sleeved dress with a belt, matched by gold accessories

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Lady Amelia complemented her twin sister in a white silk shirt and lightweight trousers, with gold accessories

Now following in her footsteps, Charles seemed all smiles as he arrived at the glittering sports event, with even the otherwise unseasonable weather holding out for the occasion.

Charles wore his favoured Moscot sunglasses coupled with a lightweight beige suit, a dapper navy, red and gold striped tie and brown suede shoes.

His appearance came just a day after the much-anticipated Trooping The Colour ceremony in London, where he was joined by the Princess of Wales for his official birthday celebration.

Both the King and his daughter-in-law, Kate Middleton, are undergoing cancer treatment, with the monarch only very recently announcing he would make a return to public duties.

In February, Buckingham Palace confirmed that he had been diagnosed with a form of cancer, which is not prostate cancer, that was discovered while the King was being treated at the private London Clinic for an enlarged prostate.

Charles initially postponed public-facing duties but resumed at the end of April, speaking of his ‘shock’ at being diagnosed with cancer as he met patients during a visit to University College Hospital Macmillan Cancer Centre in central London.

For yesterday’s occasion, King Charles III rode in a carriage with Queen Camilla, a departure from last year’s ceremony because of his illness, and he inspected the officers and guardsmen on Horse Guards Parade in Whitehall from the coach rather than from a horse.

At the polo today, Charles seemed on good form and engaging with guests around him.

The attendees included the glamorous Spencer sisters with Lady Amelia opting for a sophisticated white silk blouse and trousers, matched with gold accessories.

Her twin sister, Lady Eliza, complemented her in a white short-sleeved dress with a belt.

The siblings grew up in South Africa, but moved to the UK three years ago and have been enjoying the couture scene ever since.

Speaking to The Telegraph in 2021, the duo discussed their childhood in the wealthy suburb of Constantia in South Africa, admitting they don’t use their titles outside of the UK and had a ‘normal, happy childhood.’

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Pop Queen at the Polo: Songstress Mabel, 28, made an appearance at the prestigious event

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No Trippin today: Music maker Kara Marni wore a distinctive and stylish polka dot outfit

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Golden girl: Actress and influencer Nikkita Chadha was among attendees at the polo event

When asked about what they like to do with their father Charles, the twins referred to childhood memories.

They explained: ‘Football, competitive croquet, hide-and-seek. Growing up, the house would always be busy, full of extended family and friends.’

Other attendees at the event included popular Swedish singer Mabel, Trippin songstress Kara Marni and actress Nikkita Chadha.

Charles’ attendance at the polo coincided with Father’s Day and came just hours after The Royal Family’s X account shared footage of the King and his late father, Prince Philip, sourced from the BFI archive.

The Prince of Wales also shared a photo of him playing football with the King. The photo of William and Charles together in the gardens of Kensington Palace was taken on June 12 1984.

‘Happy Father’s Day, Pa,’ the social media post, personally signed by William, said.

The photo shows an almost two-year-old William in short dungarees and a stripey blue top and the King in a grey double-breasted suit kicking a small football.

Later that same year William would gain a younger brother, with the Duke of Sussex born in September.

King shares throwback footage as he leads tributes on Father’s Day

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