Kanye West

Kanye West

Kanye West has blasted Kim Kardashian's ex-boyfriend Ray J.

The 36-year-old rapper, who welcomed his first child, North West, with the reality TV star in June, changed the lyrics of his track 'Bound 2' to make fun of the singer's manhood during a surprise performance on 'Late Night with Jimmy Fallon' in New York on Monday (09.09.13).

He rapped: "Brandy's little sister lame man he know it now ... When a real brother hold you down, you 'sposed to drown. (sic)"

The attack is believed to be in response to Ray's song 'I Hit It First,' which he released in April and hinted he believes Kim, 32, still belongs in his bed.

The 32-year-old R&B singer, who appeared in a leaked sex tape with Kim in 2007, which kick-started her rise to fame, was previously reported to have penned the track to let Kanye know that he was Kim's first love.

The lyrics include: "She might move on to rappers and ballplayers, but we all know I hit it first.

"I had her head going North and her ass going South, but now baby chose to go West.

"No matter where she goes or who she knows, she still belongs in my bed."

A source close to Kanye previously revealed he thought the song was pathetic.

The insider said: "Kanye don't condone broke a**, jealous [guys] who be trying to bite off he and Kim's fame just to stay, wait, just to become relevant."