In recent months, reports have claimed the band are at loggerheads, especially Horner and Melanie Brown after Brown’s claim of a secret tryst at the height of their 90s fame.
But Horner insists that the group – also consisting of Emma Bunton and Melanie Chisholm – will be “celebrating together” as their first tour date approaches.
“No one is perfect but it’s all fine. We’re having a blast. It’s an absolute laugh,” Horner told The Sun.
“Our relationship is really good. We’ve all been really positive, so it’s nice. It’s natural. I’m really happy, everyone’s happy.”
Brown hit headlines back in April after claiming to have slept with Horner during a wild night at the peak of the band’s popularity.
Speaking to Piers Morgan during a recording of his Life Stories series, Brown appeared the smile and nod when the host asked if she had shared a bed “like that” with Horner.
Brown then said: “She’s going to hate me for this because she’s all posh in her country house with her husband. But it’s the past.”
Horner late denied the claims with a statement hitting out at the “hurtful” comments, which Brown also tried to backtrack on.
In a statement to Standard Online, a representative said: “It has been very disappointing to read about all these rumours again, especially on Mother’s Day of all days.
“Geri loves the Spice Girls: Emma, Melanie, Melanie and Victoria [Beckham]. She would like [the fans] 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.
The Spice Girls tour kicks off May 29 in Manchester before shows in Cardiff, Coventry and London.