Philippos married aviation heiress, Nina Flohr, on Dec. 12 at the exclusive Swiss ski resort of St. Moritz
Prince Philippos, Nina Flohr

Princess Diana’s godson, Prince Philippos of Greece, has married his long-term girlfriend in a surprise royal wedding.

The New York City-based financial analyst, who is the youngest son of King Constantine III of Greece, tied the knot with VistaJet aviation heiress, Nina Flohr, on December 12 at the exclusive Swiss ski resort of St. Moritz.

“Just married (civilly) 🤍,” Nina posted on Instagram Tuesday alongside an image of her cuddling close to Philippos in a chic white Chanel suit.

Due to Switzerland’s strict Covid-19 restrictions, only the couple’s fathers King Constantine, 80, (Prince William's godfather) and Thomas Flohr, 60, were present at the civil ceremony, which will reportedly be followed by a religious service in 2021.

Princess Beatrice’s husband Edoardo Mapelli Mozzi, who married in an equally under-the-radar royal wedding in July, was one of the first to send well wishes to the happy couple.

“Congratulations 💛,” Edo commented on Instagram, followed by a second comment featuring a dozen red heart emojis.

Nina and Philippos' engagement was first announced by the Greek royal family in September. The statement also revealed that the prince popped the question on the picture-perfect island of Ithaca.

“My dearest Philippos. I love you today, I will love you tomorrow and forever," Nina posted on Instagram shortly afterward alongside an image of the pair cuddling on a rocky hilltop overlooking the dazzling Mediterranean sea.

"You make us happier, better and stronger," she added. "I cannot wait to spend the rest our lives together 🤍🤍🤍."

Six weeks later, Nina followed this up with the equally romantic post. “Found my world in you 💚,” she wrote alongside a picture of Philippos strolling through an autumnal park.

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Away from her new-found royal status, Nina works as the creative director of her father's executive jet hire company and is the founder of the Bazaruto environmental marine research facility in Mozambique.

Together with her new husband, she also attended the royal wedding of Princess Eugenie to Jack Brooksbank in October 2018.