R&B star Ray J has laughed off rumours his controversial new song is all about his pregnant ex-girlfriend Kim Kardashian, insisting critics are reading too much into his lyrics.

The singer, who famously featured in a leaked sex tape with the reality Tv beauty in 2007, appears to take aim at Kanye West's girl in his latest release, I Hit It First, although he never references the socialite by name.

On the track, he sings, "She might move on to rappers and ballplayers/ But we all know I hit it first.../ I had her head going north and her a** going south.../ But now baby chose to go West.../ No matter where she goes or who she knows... She still belongs in my bed."

Ray J came under attack from detractors, who insisted it was in poor taste to sing about his expectant ex - who is currently stuck in a divorce battle with basketball player Kris Humphries - but the singer has brushed off the allegations.

He tells New York radio station Hot 97, "It's a song, it's not about that (taking aim at Kardashian). It's about a concept. People are going way too deep.

"I'm not trying to create no war... it's all love... It's a song, we're just having fun, that's it."