Mel B has branded Geri Horner "bats**t crazy" and Victoria Beckham a "bitch".
The outspoken 43-year-old Spice Girl poked fun at her bandmates in a tongue-in-cheek interview, where she claimed that Geri often annoys her.
Speaking to Piers Morgan on his ITV 'Life Stories' show, she said: "I love Geri to bits, but she's bats**t crazy. I'm crazy in just like a humble northern way, Geri's crazy in a different way."
Talking about the Spice Girls' group WhatsApp messages, she added: "We just say regular stuff like, 'How are the kids?' and, 'Do you agree with this contract?' and, 'Oh Geri's really annoying me'... 'Me too'. Oops, it's on group text. I forget sometimes."
She also jokingly hit out at Victoria's decision not to join the upcoming Spice Girls' reunion tour.
Asked about Victoria, she said: "A bit of a bitch but I love her. I mean, us five were together and now we're going on tour as four, you know, thank you for that [cough].
"I am sad she is not going to be there. But she is busy with what she is doing with her fashion line and her family.
"But I am gutted that she is not going to be with us. But I am still going to hold that candle and hope that she will."
In previously released quotes from the upcoming interview, it was revealed that Mel claimed she and Geri had a "one-off" fling during the band's heyday.
She said: "We were best friends. It just happened. It wasn't a thing. It just happened. We just giggled at it and that was it. It just happens one time and then you talk about it and it does not really happen again. It was just that one time."
However, Geri has denied the claims.
Her representative said in a statement: "It has been very disappointing to read about all these claims again... She would like you to know that what has been reported recently is simply not true and has been very hurtful to her family."
"Moving forward, Geri can't wait to see the girls and all the fans on the tour, have an amazing time with everyone, and make some new memories. Geri is really grateful for your support and loyalty for so many years. She loves the Spice Girls: Emma, Melanie, Melanie and Victoria."
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