British vocalist Charli XCX opens for Taylor Swift during her Reputation Stadium Tour at Gillette Stadium, Thursday, July 26, 2018, in Foxborough, Mass. Picture: AP

Charli XCX has teased fans with her version of Spice Girls' 'Wannabe' will be released on Thursday.

The girl group - now made up of Geri Horner, Emma Bunton, Mel B and Mel C, after Victoria Beckham decided against joining their reunion - gave their blessing for one of their biggest tracks to be sampled on the song 'Spicy' to aid their comeback, but they fell victim to hackers who shared the song earlier this month.

Now, Charli has revealed the release date and shared that it was her idea to get Diplo and French producer Herve Pagez on board to help her "honour" the 'Viva Forever' hitmakers with her spin on their "iconic" 1996 chart smash.

Alongside a snap of herself posing by a pool in a golden bikini, the 'Boom Clap' singer wrote on Instagram and Twitter: "looked up to the pop gods & they said "Charli - you're the chosen one: honor the spice girls' return with a mind blowing version of one of their iconic smash hits" & I said "k no probs hun I got this" so I called @diplo & @hervepagez & SPICY was born. NEW SONG DROPS THURSDAY. (sic)"

The Spice Girls' also added a wink face emoji to the comments on the post, confirming they have given their seal of approval.

Despite the leak, an insider recently teased that 'Spicy' is still going to be "huge" with an epic music video set to follow its release.

A source said: "This song has been years in the making. It's really disappointing that it's been leaked at the last minute.

"But people who have heard it seem to be loving it, which is promising ahead of its release.

"Charli sings the verses and the chorus has been mashed up and turned on its head for a really cool dance song.

"It's got an incredible video, which will be out next week.

"Sadly the Spice Girls themselves aren't in it, but it's going to be huge."

It's not the first time the Spice Girls have suffered a song hack.

In 2016, Geri, Emma and Mel B reunited in the studio to pen 'Song For Her', but that was leaked too.

Speaking at the time, Emma said: "We wrote something and it got leaked and it got stolen which is not great, but we've had nice feedback."

Meanwhile, the blonde beauty - who is nicknamed Baby Spice - previously hinted that she and her bandmates could start writing new material while they are on their reunion tour, which got underway in Dublin, Ireland, last week.

She said: "We haven't started writing or ­anything like that and it would have to be organic.

"So we'll have to see. After the tour maybe, or ­during the tour I think, especially with us girls. We're always like, 'What's next?' So it could happen. Who knows?"