James Middleton engaged to Alizee Thevenet -- see her engagement ring that looks like Kate's!

James Middleton is engaged!

The younger brother of Duchess of Cambridge Kate Middleton confirmed on Instagram on Sunday that he popped the question to girlfriend Alizee Thevenet, and that she had accepted his proposal.

"She said OUI," he captioned a selfie of them together, with Thevenet's sapphire engagement ring -- which shares a striking resemblance to that of future sister-in-law, Kate -- on firm display. "Our secret is out but we couldn’t be happier to share the news."

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On his Instagram Story, Middleton, 32, also shared a video of them swimming in the ocean together and shared an underwater kiss, as well as a montage of photos of them together.

The to-be-married couple have been dating for just over a year now, after having met at a bar in London last summer.

Middleton was first photographed with Thevenet in December 2018, and they demonstrated how serious their relationship was one month later when they went on vacation to St. Bart's with Middleton's parents. They became "Instagram official" this past May.

View this post on Instagram

Sail away with me ⛵️ ☀️

A post shared by James Middleton (@jmidy) on May 7, 2019 at 10:23am PDT

Thevenet's father, Jean-Gabriel Thevenet, spoke to the Daily Mail about his daughter's exciting new romance earlier this year, and confirmed that "they are very much in love" with one another.

"My daughter Alizee is very happy with James," he added. "James is a very charming man. I am very happy that Alizee is together with James. I know she is very happy. We keep our fingers crossed for them. I am not to say how they met, to give away their secrets."

Middleton's romance follows a tumultuous five-year relationship with "Dancing on Ice" star Donna Air came to an end in February of last year.