Mel B has sensationally claimed that she and bandmate Geri Halliwell enjoyed a steamy one night stand "back in the day".
The former Spice Girl, who is bisexual, made the explosive revelation while filming the new series of Piers Morgan's Life Stories series and explained that it just "happened" and that they "giggled" afterwards.
Not holding back, the 43 year old told Piers: "We were best friends. It just happened. Have you ever done that?
"She is going to hate me for this because she is all posh in her country house and her husband, but it’s a fact.
"It just happened and we just giggled at it and that was it."
A smug looking Piers then asked if it only happened once, to which Mel replied, "Yeah."
He then went on to gloat about the exclusive information, saying that even though fans always questioned their relationship, nothing had ever been confirmed.
“This is a bombshell. A Spice Girls bombshell. You have never admitted this before have you? People are going to be fascinated," he triumphantly added.
CHECK OUT times the Spice Girls where EVERYTHING
CLOSER Six times the Spice Girls gave us life
1 of 16When Geri wore THAT iconic dress
Geri's Union Jack dress has become synonymous with the Spice Girls and girl power in general. The dress came to be at the 1997 BRIT Awards because Geri didn't want to wear the black Gucci dress her stylist had given her...so she glued a Union Jack tea towel to the front of it. She later sold it at auction for £40,000.
2 of 16When they got the royal treatment
The Spice Girls never held back - even when meeting the monarchy. Mel C broke royal protocol by kissing Prince Charles on the cheek when she met him at a Prince's Trust concert in 1997. Meanwhile Geri went in for the kill with a pinch of the bum...
3 of 16AND when they got the royals fangirling
In the words of Regina George's mum 'I'm not a regular mom, I'm a cool mom'. If this photo isn't proof that Fergie is the COOLEST mum, then we don't know what is. Princess Eugenie and Beatrice look beyond thrilled to meet their idols.
4 of 16When Nelson Mandela admitted to being their biggest fan
The political icon famously said, "These are my heroes. This is one of the greatest moments in my life", when he met the Spice Girls in November 1997.
5 of 16And Adele too for that matter...
When the Spice Girls announced their reunion tour, Adele posted a throwback on Instagram, captioned 'HA! This is how I feel right now! I AM READY'. We feel your excitement, Adele.
6 of 16When they made a film
Released in December 1997, Spiceworld: The Movie, is arguably the film of our generation. So it's no surprise that names such as Roger Moore, Stephen Fry, Elton John, Jennifer Saunders and Richard E. Grant all wanted to get involved.
7 of 16When they finally reunited
In 2008, the Spice Girls gave us EXACTLY what we'd been dreaming of since they split in 1998 - when they announced their reunion tour. The girls even brought their babies on stage. Verdict: definitely worth the wait.
8 of 16When they showed us the true meaning of "Sporty" Spice
The Spice Girls were undoubtedly the main event at the 2012 Olympics closing ceremony in London. When they popped out of their black cabs, it's fair to say that it was the best surprise we've ever had.
9 of 16When they proved they were just like the rest of us
We didn't think it was possible to fall even more in love with the Spice Girls until we found out VB isn't so POSH after all - besides, who doesn't take part in a last minute TESCO dash at Christmas?
10 of 16AND when she showed her humour AND flexibility
Don't mind V.B, just adopting a casual pose whilst she reads through emails on her lush sofa... seriously Posh, you are one funny woman. We're already practicing the same leg-pose for when we eventually reply to work emails.
11 of 16When they decked out a London bus in the Union Jack flag
Come on... who wouldn't want to ride in the one and only spice girls tour bus!? We are OBSESSED. When can we hitch a lift?
12 of 16When Geri met Charles...
Who can forget when Geri met Prince Charles at the 1st anniversary concert for the Princes' Trust in 1997? Ginger spice certainly wasn't shy in THAT outfit - she even enjoyed a cheeky flirt with the prince.
13 of 16And then Geri and Charles reunited 22 years later
A much more sophisticated meeting this time. The pair looked like good old friends catching up as they chatted all things spice at another Princes' Trust event over two decades later.
14 of 16When London's favourite girlband took on PARIS
Bonjour Paris. Spice girls are giving us all the feels in this adorable snap in front on the Eiffel tower during their 1998 world tour. Throwback Thursday goals.
15 of 16When Posh had that haircut... but the spice girls let her have her hair moment without judgement
When Posh had that infamous haircut, the spice girls let her get on with it without passing judgement. That's true friendship, surely?
16 of 16When four of the band announced a 2019 reunion... and Posh showed her support
When four of the band announced a 2019 reunion, Posh still showed her support. Victoria took to Instagram to support her former bandmates. She said, "Today marks a special day for the girls as they announce the first tour dates since we performed together in 2012! I won't be joining my girls on stage again but being in the Spice Girls was a hugely important part of my life and I wish them so much love and fun as they go back on tour next year. I know they will put on an amazing show and the fantastic fans past and present are going to have a wonderful time! "
Mel then replied, "Yeah and I have said it now. All done. She is going to kill me and so is her husband.
"Hopefully when Geri gets asked that, which hopefully she will after this, she won’t deny it, because it was just a thing, a fun thing."
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The former X Factor host then explained why she chose to leave the juicy secret out of her new autobiography Brutally Honest, saying, "I’m an honest person. I didn’t put it in my book because that wasn’t what my book was about. It was brutally honest in a different way."
The Spice Girls are embarking on theirhighly anticipated reunion tour later this year, and fans are hoping this bombshell doesn't cause friction between the girls.
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Victoria Beckham breaks silence as Spice Girls reunite WITHOUT HER
According to The Sun, Mel put in a phone call to Geri straight after she appeared on the show.
The source explained: "The girls all know Mel struggles to keep her mouth shut but Mel C who was in the audience was visibly horrified when it all came out.
“The tour is just two months’ away they don’t want anything jeopardising it, but there were real fears this would upset Geri’s husband and cause serious issues."