The Suits actress, 35, wore a sleeveless navy dress with a white jacket draped over her shoulders as she stood in the royal box and watched her prince play in the Audi Polo Challenge at the Coworth Park Polo Club.
It marks the first time that Harry, 32, and Markle have been present at a public event together.
Prince William‘s former Eton classmate Eddie Redmayne and Dr. Who star Matt Smith (who portrays Harry and William’s grandfather Prince Philip in the Netflix drama The Crown) were also in attendance at the event, which raised funds for two of Harry’s charities, Sentebale and WellChild.
The Telegraph reports that Markle was accompanied by Mark Dyer — a former Welsh Guards officer and Prince Charles’ former equerry, who is very close to Harry — and Dyer’s American wife, Amanda Kline.
Markle could be seen clapping and smiling as she watched Harry, who she has been dating since last summer.
As Us Weekly previously reported, Markle will be Harry’s plus-one at the nuptials of Middleton and her fiancé, James Matthews, at St. Mark’s Church Englefield in Berkshire on May 20.
William and Kate will also be in attendance and their children, Prince George, 3, and Princess Charlotte, 2, will have key roles as page boy and bridesmaid at the wedding.
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