Simon Cowell and Alesha Dixon have reportedly had a bust-up at the Britain's Got Talent Birmingham auditions.
Cowell apparently taunted his new co-star by asking her, "Who are you?" after they fell out over a dance group act called Lil' Diamondz.
Lil' Diamondz have appeared on Dixon's CBBC series Street Dance Stars and the reality TV judge told the act that they "hadn't let her down" following their audition.
However, Cowell mocked Dixon for her comments, complaining: "What a silly comment to make. That's a silly thing to say, Alesha... Sorry, who are you, anyway?"
According to The Mirror, the spat continued backstage and Dixon "stormed off to her dressing room".
A source close to Cowell insisted that his remarks were "harmless banter".
Britain's Got Talent returns to ITV1 in the spring.
