The 44-year-old, who launched a successful solo career after the girl band split in 2000, is said to have convinced Geri Horner a.k.a. Geri Halliwell, Melanie Brown and Emma Bunton to refresh their vocals ahead of their reported comeback next year (19).
According to editors at The Sun, Mel C has taken charge and wants the group to perform alongside a live band to make their pop hits current.
The four women, minus former bandmate Victoria Beckham a.k.a. Victoria Adams, are apparently planning to reunite for a 13-date stadium tour, which will culminate with three nights at Wembley Stadium in London.
Manager Simon Fuller is masterminding the comeback, which could net each performer an estimated $15.7 million (£12 million) each.
Addressing the reunion on U.K. chat show "Loose Women" last month, Mel B, aka Scary Spice, told the panel: "There is a reunion happening for sure. I'm not supposed to say when but it is happening."
She did confirm that whoever isn't confirmed would be taking part in "guest appearances" during the tour.
And when asked if all five girls were taking part, Mel B said: "Yes... kind of. Does that make any sense? Nothing is making any sense to me this morning. It's definitely four of us."
Co-host Nadia Sawalha challenged the mother-of-three on whether the reunion would take place at all, and disputed her confirmation, leading to Mel B inadvertently revealing that tour dates have been decided on.
Talking to Nadia, she said: "I told you a date earlier off camera." The presenter then replied: "You haven't given me a ticket - that's why I don't believe you yet."