Meghan Markle: Who could design the dress for the next royal wedding?

When Prince Harry and Meghan Markle posed for photos after announcing their engagement on Monday, Ms Markle wore a white coat from a brand called Line the Label.

The Canadian brand's website then received so many visitors it crashed under the volume of traffic.

It proves the world's eyes are now firmly watching the US actress - and what she wears - ahead of the royal wedding.

Clarence House announced the couple will marry in spring 2018, which - as any bride-to-be will know - means Ms Markle needs to act quickly to find her perfect wedding dress. So which designer will she choose?

Asked what she would wear to walk down the aisle, Ms Markle previously told Hello! magazine her perfect dress would be "classic and simple".

She made the comments after her character in the US legal drama Suits got married, adding: "I personally prefer dresses that are whimsical or subtly romantic".

"She is covering all bases there," says Katie Rosseinsky, a fashion writer for Grazia Daily.

"She's been photographed wearing Erdem and Antonio Berardi recently. Erdem has that whimsical element of design which she likes, so that could be an option."

British designer Berardi on the other hand is famed for the classic and simple look which Ms Markle says she favours.

"I could also see her in something a bit more directional like Emilia Wickstead, who is also one of Kate's favourite designers," says Rosseinsky.

"It would be a cool option, not super-embellished, but with interesting shapes that photograph well."

Rosseinsky describes Ms Markle - who appeared at the Invictus Games in Toronto in ripped jeans in September - as "a relaxed, casual dresser".

"It's very different to the coat dresses we see Kate [the Duchess of Cambridge] and other royals wearing. Will she be compelled to smarten up?" asks Rosseinsky.

Jodie Davis, co-executive producer of TV show Entertainment Tonight Canada, thinks the wedding will have some Canadian input, as Ms Markle lived there for more than six years while filming Suits.

Davis says those ripped jeans at the Invictus Games sold out after the 36-year-old appeared in them.

"It became the 'it' look in the city," he says, adding that Ms Markle made the Toronto Life magazine's list of most influential people during her time there.

Davis says he thinks there will be "ethical brands from the US and Canada" involved in the wedding, reflecting Markle's charity work.

"There are rumours there will be a Canadian influence in the wedding photos or the dress itself," he says.

"She definitely brings a very relaxed but stylish and chic look when she's out and about. She's the opposite to the character in Suits, which is well tailored power-dressing."

Christine Ross, who is the editorial director of Meghan's Mirror - a fashion blog chronicling Ms Markle's style - agrees.

"Her style hasn't changed since before Harry - it's quite modern and edgy but with a bohemian softness, so it's a relaxed vibe," she says.

"I expect her wedding dress will be quite classic but modern and structural. She will pick a diplomatic brand - with a British or American choice. She will be demure with maybe a crisp satin, but definitely modern."

Ross says while the Duchess of Cambridge has a "traditional" look, Ms Markle "will be a bit more trendy and fearless".

"It's because she's an American - the culture is a lot different," she explains "Kate is an upper middle class British girl and Meghan grew up in LA, it's a completely different lifestyle."

Mark Niemierko, a celebrity wedding planner, says he's "excited and intrigued" by what form the wedding will take.

"She could choose a Vera Wang, or Oscar de la Renta, Monique Lhuillier is also very chic, very classic," he says naming three of the most respected American dress design houses.

"If she goes down the British route it could be Christopher Bailey at Burberry. Another really good option would be Stella McCartney, which would play into Meghan's ethical credentials.

"Alice Temperley is also really ethical, but would be a bit slinky, so it would really depend on the location. If you're getting married at Westminster Abbey you need a dress to fill it."

Niemierko, who planned James Corden's wedding to Julia Carey in 2012, adds: "Meghan is not from British high society and there is a whole new raft of people at British Vogue who are also not from society.

"Alexandra Schulman [the former British Vogue editor] played a big part in advising Kate for her wedding dress. So Edward Enninful might be a great influence. That would be really interesting."

But on the other hand, it may even be US Vogue editor Anna Wintour who advises Ms Markle.

"Wintour is incredibly powerful and takes great personal interest in things like this," says Niemerko. "Harry will play his part. He's the young, cool one. He'll be encouraging her to be herself."

Whatever happens, certain to be a big influence is Jessica Mulroney, a friend and stylist to Ms Markle.

Mulroney is also the stylist for Canada's first lady, Sophie Trudeau, and runs a New York wedding boutique.

"They're very close friends," says Grazia's Rosseinsky, who thinks Mulroney's influence on Ms Markle is clear.

"If you look at the earlier photos of Meghan, she's definitely become more polished. I think that's definitely the influence of Jessica Mulroney.

"When you style one of the most powerful and most photographed women in the world like Sophie Trudeau, you will definitely bring some tips across."

The fashion writer thinks Mulroney will not only play a part in the look of Prince Harry's wife-to-be for the pending nuptials, but also in the future.

"I imagine she will definitely be involved in the wedding," she says. "She will also be very good for diplomatic dressing. Kate is good at throwing a nod to labels from the countries she's visiting. Jessica Mulroney will be already used to this from styling Sophie Trudeau."

Wedding planner Niemerko adds that whatever Ms Markle's choice of dress, only one thing is important.

"The most exciting thing about the wedding is being yourselves," he says. "They're marrying for love - which is the best way."

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