Popbitches: The Rivals

The battle for the Christmas number one descended into bitching today when Pete Waterman, who looks after boy band One True Voice, claimed that his chart rivals Girls Aloud had used professional session singers on their single.

Waterman hit out at Louis Walsh's girl band on Capital Radio, saying he had heard their song, Sound Of The Underground, in September and that the new version simply had the girl's voices added over those of other singers.

His comments immediately escalated into a war of words between Walsh and Waterman. The two bands, from the Popstars: The Rivals TV show, are fighting to take the coveted top Christmas slot, which is announced on Sunday.

Waterman said: "It's a smashing pop record - there's no question about it. But they're not on it. So what's the point in going into a competition. I have heard that record since September. The version I heard in September is no different - it's just got four of the girls' voices on. Listen to the choruses - they're session singers. It's not all the girls."

Furious Walsh phoned the radio station minutes later to tackle the accusation. He said: "The man's a liar - he's just running scared. This man is a bully - he's so out of touch that he's actually telling lies. Everyone should know that Pete Waterman is a liar. He's got away with being a liar for years because of the Stock Aitken Waterman connection. This man is out of control and he's telling lies to the British public. He knows the girls are amazing - he's heard them all sing live in the studio.'

Walsh spoke out directly to Waterman: "You're an old man at the end of your career - just go out on top. Go out and go out decently and don't try to make these girls out to be something they're not. You know they're going to have a Christmas number one. Do you really think you'll get away with lying?"

Hitting out at One True Voice, he said: "They're no Westlife or Blue, they're just a boy band. The girls are ahead, the boys are suffering. The boys are like a Westlife tribute band. He's good at tribute bands - his last band Steps were an Abba tribute band."

The row came hours after One True Voice attacked Girls Aloud claiming they had "no talent". Keith Semple, one of the five voted into the band by ITV viewers, said: "The girls are trying everything they can to get to number one but they haven't got the talent. The fight is far from over. Even if they have got a slight lead, they've still got a big fight on their hands."

Fellow member Daniel Pearce said: "The girls can't sing live. They can't harmonise. When they tried to record their single for SM:TV, they were so bad they ended up miming."

Sales of the girls' single on the first day of release were 40,848 - 8,000 ahead of the boys' song, Sacred Trust.