Rosie O'Donnell and girlfriend Michelle Rounds are engaged to be married.

O'Donnell reportedly announced the news to her The Rosie Show studio audience in Chicago during a commercial break on Monday. O'Donnell's show premiered in October on Oprah Winfrey's OWN network.

“They are looking forward to spending the rest of their lives together,” an unnamed O'Donnell rep told The New York Daily News.

“Mazel on your engagement,” Bravo's Andy Cohen tweeted.

“Thanks Andy,” O'Donnell replied, “I am very happy.”

During an interview with ABC's Nightline before the premiere of her new show, O'Donnell, 49, talked about meeting Rounds, a New York City headhunter.

“I walked into a Starbucks in the summer and she was holding a little puppy,” O'Donnell said. “I thought she was a 28-year-old heterosexual girl, because that's what she looked like to me. And she's a 40-year-old gay woman.”

“My gaydar was way off!” she said with a laugh.

“I think if I had known that she was gay, I wouldn't have been brave enough to talk to her,” O'Donnell added.

This is the second marriage for O'Donnell, who came out gay in 2002 and shares 4 children with ex-wife Kelli Carpenter.

Us Weekly is reporting that O'Donnell told her audience that she and Rounds will tie the knot over Christmas.