Rihanna, Chris Brown 'Just Friends'

Noel Vasquez/Getty Images|Mindy Small/FilmMagic

Chris Brown is not cheating on his current girlfriend with ex Rihanna, contrary to rumors.

Responding to a report in Us Weekly, Brown's rep, Jeff Raymond, told ABCNews.com, "He and Rihanna are just friends," adding, "He is with his girlfriend, Karrueche, and is not cheating."

That would be aspiring model, who has been dating the R&B singer for several months and recently rang in the new year with him at the Las Vegas club where he was hosting an NYE party.

Despite their appearances together and a new tattoo Brown was seen sporting with an obvious likeness to Tran's face, rumors persist that Brown still has a thing for his ex.

According to Us Weekly, the former couple has been secretly "hooking up" for nearly a year, though a court order stemming from Brown's infamous assault on Rihanna requires them to remain apart. A Brown source is quoted saying, "She comes to see him anytime she's in L.A."

"Rihanna loves to live dangerously, and talking to and hooking up with Chris is all part of that," a Rihanna insider is quoted saying in the Us report.

Rihanna's rep did not respond immediately to ABCNews.com's request for comment.

But the "Umbrella" singer's recent tweets with Brown seemed to imply the flame was still burning. On Dec. 29, Brown, who follows Rihanna on Twitter, tweeted, "Love U more than u know!" A minute later, Rihanna, who follows Brown on Twitter, tweeted, "I'll always love u #1LOVE."

The tweets may have taken an ugly turn days later after Brown was photographed with Tran on New Year's Eve.

"How can you lie to her, while u lay with me???…..If you don't have an answer, you don't have to answer," Rihanna tweeted, presumably to Brown.

February 8 marks the three-year anniversary of Brown's assault, to which he pled guilty and was sentenced to community service and five years probation.

Chris Brown and Karrueche Tran (credit: FameFlynet)