The square-cut sparkler sits on a diamond-covered band

By Kate Hogan
Updated April 02, 2012 09:00 PM

Splash News Online

A 30-carat Rock? Not quite, but the engagement ring Alec Baldwin presented to girlfriend Hilaria Thomas over the weekend definitely is stunning. The bauble — seen on Thomas Monday while she was out in New York — features what appears to be a square-cut diamond set on a diamond-covered band.

“Yes, it’s true! Alec proposed to Hilaria this weekend and we’re all excited for the newly engaged couple,” a rep for Baldwin tells PEOPLE. “Alec’s birthday is tomorrow — great way to celebrate!”

The 30 Rock star began dating Thomas, a yoga instructor, last summer.

“I’ve got a woman in my life now,” the actor said of his love not long ago. “My girlfriend is very important to me.”

Baldwin was previously married to actress Kim Basinger, with whom he has a 16-year-old daughter, Ireland.