Scarlett Johansson engaged

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Scarlett Johansson is engaged to her beau, journalist Romain Dauriac, PEOPLE has learned exclusively.

"They're engaged and very happy," a source says of the couple. A rep for the actress had no comment.

The proposal occurred about a month ago. The ring is a vintage Art Deco ring.

Earlier this week, the actress, 28, was spotted wearing the diamond stunner while in Italy promoting her new sci-fi film Under the Skin at the Venice International Film Festival.

Over the past year, Johansson had been spotted wearing diamond rings on her left hand. The last time was in July, when she arrived in Los Angeles wearing an ornate gold ring with a diamond and ruby. That bauble, though, was "simply a piece of jewelry."

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