Kate and Meghan check with the Queen about their outfits

The Duchess of Cambridge and the Duchess of Sussex swap notes with the Queen about what they’re wearing before a joint engagement with her.

Royal commentator Omid Scobie tells Yahoo UK’s ‘The Royal Box,’: “It’s quite normal for a private assistant to Kate to check in with the Queen’s private secretary and find out what she’s wearing so you don’t clash or sort of take the colour that she’s picked to wear that day.”

When Her Majesty and Meghan had their first joint engagement in Cheshire last year, the Queen chose one of her signature block colour coats in lime green, while her granddaughter-in-law opted for a neutral Givenchy dress to complement her.

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Similarly, when the Queen and Kate visited King’s College London, the monarch stood out in a pale pink coat, while the Duchess of Cambridge wore a grey Catherine Walker dress.

It’s also been noted that when the Royal Family all get together, there is often a common theme or colour to their outfits. On the first day of Ascot in June, the Queen, Kate, Princess Beatrice, Princess Eugenie and Zara Tindall wore looks in different shades of blue.

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Scobie adds: “I think one thing that Meghan and Kate really share in common is that they’re both very mindful dressers...there’s always that extra attention to detail.”

The duchesses both know the art of sartorial diplomacy, particularly when it comes to royal tours.

Their outfits usually include nods to the host nation either through the choice of designer, the colour in relation to the country’s flag or by a piece of symbolic jewellery.

During the Duke and Duchess of Sussex’s tour of New Zealand, Fiji, Tonga and Australia last October, Meghan’s first outfit was a white dress by Australian designer Karen Gee. There was also a nod to Tongan red as she landed on the island wearing a scarlet Self Portrait number.

The Duchess of Cambridge has borrowed brooches from the Queen’s collection for her overseas visits, most notably the Maple Leaf in Canada and the silver Fern in New Zealand.

Kate is also renowned for her literal dressing - a floral Erdem dress for the Chelsea Flower Show, a nautical outfit for a visit to the Cutty Sark in Greenwich wearing a Breton stripe top and LK Bennett sailor-style trousers.

Meghan uses subtle but clever style tricks to convey a message, for example, her purple Aritzia dress and red Sentaler coat combo to visit Birkenhead in January appeared to be a nod to the logo of Tomorrow’s Women Wirral.