In pictures published in Mail Online, the royal mum-to-be looked elegant in a teal coat and a black pleated dress as she joined her brother-in-law Edoardo Mapelli Mozzi for lunch at Harry's Bar in Mayfair on Tuesday.
Pregnant Eugenie, 30, showed off a hint of a baby bump in her autumnal outfit as she left the Italian restaurant with her older sister Princess Beatrice's husband.
WATCH: A timeline of Eugenie and Jack's love story
In keeping with UK guidelines, Eugenie also donned a printed face mask, and she wore her brunette locks in a loose bun.
Meanwhile, property developer Edoardo, who married Princess Beatrice in July, chose a navy suit with an open-collared white shirt.
Eugenie and husband Jack, who are set to celebrate their second wedding anniversary on 12 October, announced their baby news with an adorable Instagram post on Friday. It featured photos of the parents-to-be beaming at the camera together and holding a pair of John Lewis bear slippers. The Princess, 30, wrote: "Jack and I are so excited for early 2021..."
Eugenie and Jack are expecting their first child in early 2021
The official statement from Buckingham Palace read: "Her Royal Highness Princess Eugenie and Mr Jack Brooksbank are very pleased to announce that they are expecting a baby in early 2021.
"The Duke of York and Sarah, Duchess of York, Mr and Mrs George Brooksbank, The Queen and The Duke of Edinburgh are delighted with the news."
The royal baby will be 11th in line to the throne when he or she is born and will be the Queen and the Duke of Edinburgh's ninth great-grandchild.
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