For the first time, Chris Brown is speaking out publicly – and apologizing – for assaulting Rihanna earlier this year.

"Since February my attorney has advised me not to speak out even though ever since the incident I wanted to publicly express my deepest regret and accept full responsibility," Brown says in a new video message posted to his official Web site. "I felt it was time [that] you hear directly from me that I am sorry."

"I cannot go into what happened, and most importantly am not going to sit here and make any excuses," Brown, 20, says in the message. "I take great pride in me being able to exercise self control, and what I did was inexcusable. I am very saddened and very ashamed of what I have done. My mother and my spiritual teachers have taught me way better than that."

Last month, Brown pleaded guilty to felony assault in a plea bargain with prosecutors, sparring him jail time. As part of the deal, he'll be sentenced to five years probation and six months of community labor to be served in Virginia. He will also complete a year of domestic violence classes, and pay fines.

Brown is forbidden from phoning, e-mailing or texting Rihanna, and can't come within 50 yards of her (10 yards at music industry events) until his Aug. 5 sentencing, when the judge will consider Rihanna's request for a less-restrictive order.

"I have told Rihanna countless times, and I am telling you today, that I am truly sorry and that I wasn't able to handle the situation both differently and better," Brown continues.