The Grand Ducal Court of Luxembourg announced the happy news on Tuesday that Prince Louis is engaged to Scarlett-Lauren Sirgue.
Three new photos released show the happy couple beaming at the camera, dressed casually in knitwear, with a gold engagement ring visible on Scarlett-Lauren's left hand.
In two more formal portraits, Prince Louis wears a suit jacket with a pale blue shirt, matching his fiancée in her chic cornflower blue top and trousers.
The couple were first pictured publicly together in March 2020
A third image shows the newly-engaged couple posing with Prince Louis' parents, Grand Duke Henri and Grand Duchess Maria Teresa of Luxembourg.
The 34-year-old prince was previously married to Tessy Antony, now known as Tessy Antony de Nassau, whom he shares two sons with, Prince Gabriel, 15, and Prince Noah, 13.
In February, Tessy revealed she is expecting her first child with fiancé and Swiss businessman Frank Floessel.
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Louis gave up his succession rights and those of his descendants upon his marriage to Tessy Antony in 2006.
In a statement, the royal court said: "We are happy to announce the engagement of our son, Prince Louis, to Miss Scarlett-Lauren Sirgue.
"Princes Gabriel and Noah join us in surrounding the new couple with all our affection. We wish them immense happiness."
The couple with Grand Duke Henri and Grand Duchess Maria Teresa of Luxembourg
Scarlett-Lauren, who was born in Bordeaux on 8 August 1991, is the youngest child of Pierre Sirgue and Scarlett Sigrue, who are both lawyers.
She followed in her parents' footsteps and was admitted to the Paris Bar at the age of 23 and sworn in at 25.
Scarlett-Lauren began her career as a lawyer alongside her mother in Family Law, but she now specialises in Victims' Law, working for the firm founded by her parents.
Her future husband, Louis, also works at the firm as a mediator.
A date for the royal wedding has not been set yet.
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