The Duke of Sussex was pictured arriving back in the US on the eve of the Queen's 95th birthday.
And for royal fans who may be wondering why Harry didn't extend his stay in Windsor to spend more time with his grandmother, it seems the Duke had an important meeting scheduled in his diary.
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According to Page Six, Harry had an alfresco lunch with American philanthropist Wallis Annenberg at San Vicente Bungalows in West Hollywood, Los Angeles on Wednesday – the day of his grandmother's birthday. The exclusive members club bans the use of mobile phones or picture-taking, making it the perfect place for the rich and famous to meet in private.
WATCH: Prince Harry and Kate share a moment after Prince Philip's funeral
The report revealed that Harry and Ms Annenberg, 81, sat outside, away from other guests, and that the Duke walked in wearing a face mask. Harry's spokesperson refused to comment on the report.
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Prince Charles' son had just landed in California on an American Airlines flight the afternoon before. It's not known whether he has been vaccinated, or whether he planned to quarantine in his Santa Barbara home, but LA guidelines say travellers are exempt from self-isolating for work purposes.
© Photo: Getty ImagesHarry had lunch with American philanthropist Wallis Annenberg
His business meeting may not come as a total surprise given the royal family's close links with the Annenberg family. Ms Annenberg's father, Walter Annenberg, served as the US ambassador to the UK under President Nixon's term from 1969 to 1974.
His heiress daughter Wallis is President and Chairwoman of the Board of The Annenberg Foundation, a multibillion-dollar philanthropic organisation that supports causes including environmental stewardship, social justice and animal welfare – issues that Harry and his wife Meghan both champion.
© Photo: Getty ImagesPrince Harry walked in Prince Philip's funeral procession
Harry returned to the UK for a fleeting visit this month to attend his grandfather Prince Philip's funeral in Windsor on Saturday 17 April. Royal watchers had queried whether the father-of-one would remain in the UK for a few days longer to see in Her Majesty's milestone birthday, but Harry flew back the day before.
He and his wife Meghan did, however, share a special gift with the monarch and sent her birthday wishes alongside their son Archie, HELLO! can confirm.
On her actual birthday, the Queen shared a heartfelt statement, thanking the public for their kindness and support during this "period of great sadness", while the palace noted that she was spending the day in mourning at Windsor Castle.
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