The Duke and Duchess of Sussex enjoyed their first official engagement as a married couple today as they attended Prince Charles’ 70th birthday celebrations.

The garden party, which was held at Buckingham Palace, was the perfect opportunity for Prince Harry, 33, and Meghan Markle, 36, to step out together just days after their fairytale wedding.

The former Suits actress looked stunning in a sophisticated £590 dress by Goat which fell just below the knee.

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Meghan’s brunette locks were worn in a sleek up-do and she accessorised her look with a Philip Treacy hat and a Wilbur & Gussie clutch bag.

The new Duchess kept her jewellery minimal and let her sparkling wedding ring take centre stage as she stood alongside the Duchess of Cornwall, who was dress in a mint green ensemble.

Meghan completed her new look with a pair of sheer, flesh-coloured tights. In addition to nude nail polish, the ladies of the royal family are also expected to cover up their bare legs when appearing in public.

For the first time, she will be addressed as Her Royal Highness – HRH – in public and people will be expected to curtsey to her and called her Ma’am.

Asked whether Meghan would be insisting on royal protocol being enforced, Kensington Palace reportedly declined to comment.

Meanwhile, Prince Harry looked very smart wearing a pair of grey striped trousers and a cream waistcoat, which he teamed with a blue tie as he helped celebrate his father’s milestone birthday. The couple are said to have delayed their honeymoon in order to attend the party.

The Duke of Cornwall’s real birthday falls on November 14, but it seems May was a more appropriate month to hold a garden party thanks to the sunny weather.

His official website stated: “The event will celebrate The Prince of Wales’ Patronages and Military affiliations as well as others involved in charities supported by The Prince.”

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Therefore, more than 6,000 guests from 386 of The Prince of Wales’ patronages were invited to the event, which was hosted by the Queen.

In addition, 20 of the Prince’s military affiliations were represented, as well as 100 Cadets from Youth United.

According to reports, Prince Charles wanted to use the garden party as an excuse to thank his charities and patronages for their work over the years.

Last weekend, Prince Charles walked his new daughter-in-law down the aisle at St George’s Chapel at Windsor Castle before she said ‘I do’ to his younger son.

Prince Charles then hosted the evening reception at Frogmore House, which was attended by the likes of George Clooney, David Beckham and the cast of Suits.

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Guests dined on posh burgers among other dishes, with candyfloss on offer to those with a sweet tooth. The party featured music performed by Sir Elton John, who famously sang a rendition of Candle in the Wind at the groom’s mother Princess Diana’s funeral in 1997.

From our sister site Woman&Home. Words by Kirsty McCormack.