Rihanna at the 20th Annual Nickelodeon's Kids' Choice Awards 2008 held at UCLA Pauley Pavilion. Westwood, California - 29.3.08

The pair has caused much speculation over the nature of their relationship since they were photographed frolicking in a Jamaican swimming pool together last month (Feb08).

They further fuelled rumours last month (Mar08) after they were photographed leaving a London hotel together - but the Umbrella star insists Brown is more like a family member than a love interest.

She says, "I won't say that we're just friends - me and Chris are really best, best friends. We both started our careers around the same time. He is one of the only people in the industry ... I trust and hang out with all the time.

"We are best friends, honestly, like brother and sister. If he was a boyfriend, I would say that."

Source: WENN