The couple, who got engaged less than a month ago, are reportedly already planning to get married this year.
Millie's Made In Chelsea co-star, Oliver Proudlock, apparently let slip their plans during his gallery opening.
When asked about the couple's nuptials, he told OK! Online: "I think they will get married in the summer."
Millie looked gorgeous as she and Pro Green celebrated their nuptials with an official engagement party on Friday night.
The 23-year-old looked stunning in a cream Shakuhachi snakeskin dress with a sheer-panelled hemline.
Millie has already been shopping for her dream wedding dress, posting a picture of herself on Instagram trying on a cat veil last week.
She tweeted: "Trying on wedding dresses today.. Possibly the most excited I've ever been about shopping!"
Pro Green popped the question during a romantic trip to Paris, getting down on one knee to ask for Millie's hand in marriage.
She in turn took to Twitter to tell the world their news, adding: "If I could scream loud enough for the whole world to hear I would."
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