So here's a story from A to Z: The Spice Girls wannabe back on stage!

Melanie "Scary Spice" BrownMelanie "Sporty Spice" ChisholmEmma "Baby Spice" Bunton, and Geri "Ginger Spice" Halliwell are planning a reunion tour, a source exclusively reveals in the latest issue of Us Weekly.

"This has been in the works for the past year," the insider tells Us. "The girls have long been keen to do a major reunion tour together."

Unfortunately, one member of the 1990s pop sensation — Victoria "Posh Spice" Beckham — isn't so eager to strap on her platforms.

"They are trying to convince Victoria to jump in, but she doesn't want to do it," a second source tells Us.

But rest assured, should Posh, 41, decide to sit out, the show will still go on. Says the second insider: "If she doesn't agree, they are moving ahead without her."

Whether Posh will have some sort of involvement is still up in the air. "She won't sing or dance," reveals the first source of the fashion designer and wife of former soccer pro David Beckham, adding, "There's a small chance she'll film something with them or make an appearance at a show here and there."

Rumors of a reunion tour have been swirling for months. Although the British pop stars have not yet confirmed that plans for a tour are in motion, they have been very open about loving the idea.

"We adore each other," Bunton, 40, told the Telegraph on March 21. "I would love to do something."

"It's our 20th anniversary this year, and it would be rude not to celebrate," Brown, 40, said on a U.K. television special in December. "So hopefully something will be happening pretty soon."

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