US R&B star Chris Brown telephoned his girlfriend Rihanna on her birthday in order to apologise for his alleged attack on the singer, it's been reported.

Brown is believed to have tried to make contact with the singer last Friday (February 20th), and has apparently sent her gifts including an iPod Touch.

“He’s absolutely trying to get back into her good graces,” a source told the New York Daily News.

“He knows he’s very much in the doghouse right now, and is doing everything he can to show her how sorry he is.”

Brown was questioned by police earlier this month following a complaint of assault from an unknown woman, reported to be Rihanna.

Brown and the woman are believed to have got into an argument in the Hancock Park area of Los Angeles.

As previously reported, a photo believed to be of Rihanna, which showed her with extensive facial injuries, emerged online last week.

In a statement on Saturday (February 21st), Rihanna's spokesperson said: "At the request of the authorities, Rihanna is not commenting about the incident involving Chris Brown.”

Her spokesperson added that the singer wanted to “assure her fans that she remains strong”.

Brown has already apologised over the incident and has said he is seeking counselling.

Both Brown and Rihanna missed the Grammy Awards on February 8th - the day of the alleged assault.

(by Jason Gregory)