Scarlett Johansson and Ryan Reynolds engaged

Scarlett Johansson is set to marry her beau Ryan Reynolds, the actress' rep, Marcel Pariseau, has confirmed.

"They're both thrilled," says Pariseau.

Johansson, 23, and Reynolds, 31, have been dating since Spring 2007. The couple have not set a wedding date.

The Lost in Translation star is expected to show off her engagement ring at Monday night's Metropolitan Museum Costume Institute Gala in New York. Sources close to the actress say she is eager to "show off her rock" with her Dolce & Gabbana gown.

Johansson was previously dating Josh Hartnett. Reynolds was previously engaged to Alanis Morissette.

In February, it was reported that Scarlett was seen shopping for wedding dresses at a Monique Lhuillier boutique in L.A. with her mother and sister.

But her rep denied any pending nuptials between the pair, insisting, "A family member is getting married, not her. She is not engaged."

Johansson will next be seen in Woody Allen's Vicky Cristina Barcelona and the Drew Barrymore-produced He's Just Not That Into You. Reynolds has several upcoming projects including Fireflies in the Garden with Julia Roberts and X-Men Origins: Wolverine.