'The most glorious day!' Mel C shares nostalgic Spice Girls throwback snap amid claims she plans to sue Emma Geri and Mel B over reunion plans

She's allegedly planning to sue her former bandmates Emma Bunton, Geri Horner and Mel B over their plans to reunite as a three-piece to mark the Spice Girls' 20th anniversary.

Yet all seemed to be well on Mel C's Instagram page as she shared a sweet throwback snap of the celebrated band reuniting for the 2012 London Olympics.

'The most glorious day! #London2012 #spiceupyourlife ✌4 years ago! Wow! Thanks @leolondon85,' the singer, 42, captioned the comeback shot where they set London alight with their feel good nostalgia four years prior. 

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Nostalgic: Mel C, 42, shared a sweet snap of the Spice Girls re-uniting for 2012's London Olympics, amid claims she's planning to sue her former bandmates

This comes after Sporty Spice Mel, is said to be consulting lawyers in the bid to block her former bandmates' plans to form pop trio GEM.

Mel herself reportedly declined offers to take part in the reunion, along with fifth member, Victoria Beckham.

A source told The Sun: 'Mel has told the other girls she is consulting lawyers about whether the reunion can go ahead without her.

'She believes she brought music credibility to the group and there is no Spice Girls without her.

There was talk of using the nickname GEM but they’ve decided against that because the strength is through the Spice brand.'

Taking action: Mel is allegedly unhappy about her former bandmates' plans to form pop trio GEM and is said to have been consulting lawyers in a bid to block the reunion

The newspaper also reports that the girls are still on good terms and in regular contact.

It's thought the trio are still going ahead with their plans for a pop comeback regardless, and are alleged to be planning a massive comeback concert in London's Hyde Park.

MailOnline has contacted representatives for Mel C for comment. 

Three-piece: It was announced last month that Emma Bunton, Geri Horner and Mel B would be reuniting as a three-piece to mark the Spice Girls' 20th anniversary

The three-piece have already begun recording new material for their upcoming reunion including a track called Song For Her, according to an earlier report by The Sun.

Nine years on from the girls' original comeback single Headlines (Friendship Never Ends), the leaked tune contains the lyrics, 'Wipe up your tears of doubt you have been crying, lift up your dreams feel like you’re flying, never forget the girl is the woman you are.'

Speaking further to The Sun, the source mentioned, 'It will not be released under the GEM name that they gave themselves in their announcement, this is still very much the Spice Girls.'  

Say You Won't Be There! Mel C (second left) and Victoria Beckham (far right) will not be joining them for the reunion 

In a 40-second clip released to YouTube last month, Geri, Emma and Mel announced that they'll be staging a reunion in commemoration of the band's 20th anniversary. 

With Victoria and Mel C opting not to return to the group, the remaining three have renamed themselves GEM - an acronym of the singers' first name initials.

With the instrumental from their 1996 hit debut single Wannabe playing in the background, Mel B is first to pop up on screen, saying: 'We've been thinking... We have the best fans in the entire world.' 

Five Become Three! The girls confirmed they're reuniting as a trio now called GEM in a lip uploaded to YouTube last month

'You've stood by us for 20 years, and we wanna say a big thank you,' adds Geri.

Emma, who was known as Baby Spice in the band's heyday, adds with a glowing smile: 'We've had our ups and downs, but you've always been there.'

Continues Mel B: 'And we wanna celebrate and have a party. And when we do...'

'You're all invited!' Geri, Emma and Mel yell with excitement as the clip comes to a close.

Precious GEMs: The remaining trio's new moniker is an acronym of Geri, Emma and Mel's first names

Start spreading the news: Mel B is the first of the new trio to address fans in the newly-released 40-second clip

Youthful glow: Emma, who turned 40 at the start of the year, appeared to have barely aged since her '90s debut

Once the split screen of the stars fades out, a message to fans of the group reads: 'Happy 20th birthday to all our fans. This is a celebration for you!

'We hope to tell you soon what you want. What you really really want. #Wannabe.'

It had previously been reported that the ladies met at Geri Horner's home recently where they hashed out the plan to celebrate their iconic single Wannabe turning 20.

Quit: Geri Horner, previously known as Ginger Spice, sensationally quit the band at its height in the 1990s

Separate project: Before the official announcement, Mel revealed that she's working on her own album

Gratitude: The stars have said that they're reuniting as a way of saying thank you to their committed fans

However, until recently all plans appeared to be off, as the reality began to sink in that Victoria and Mel C were not going to be a part of the reunion. 

A source told The Mirror recently: 'Mel C has been telling friends it's not happening – not for the anniversary and not next year.

'She's not interested in revisiting the band, and neither is Victoria. Their decision has made it impossible for the other three to go ahead with plans to tour again.'  

Stage presence: Mel and all of her bandmates staged a much talked-about reunion tour in 2007

 The way they were: The band, seen at the 1998 Brit Awards, dominated the charts internationally in the 1990s

Change of heart? It had been reported that Mel C was uncertain. However, she is now out of the reunion 

And earlier in the year, a source close to the Liverpudlian singer told The Sun it was unlikely she would rejoin the group. 

Meanwhile, Victoria has turned her back on music once and for all and is focused on her successful designer fashion range.

Her rep previously said: 'Victoria has been very respectful about the fabulous time they had together in the past, however her focus is now very much her family and fashion business.'

All smiles! Victoria had long declined to work with her former group - which propelled her to fame in the 1990s

Old friends! It had been expected the group would mount an imminent return for their anniversary and a number of hints had been dropped by some of the girls

The Spice Girls formed in 1994 and became one of the world's most popular British pop groups since the Beatles after their debut single Wannabe hit the charts in 1996.

During their nineties heyday, the group managed to sell more than 80million records, making them the best-selling female group of all time.  

After a seven year hiatus, they reunited in 2007 and embarked on a global tour and their Greatest Hits album peaked at No.2 on the UK Album Chart.

The girls last performed together at the closing ceremony of the London 2012 Olympics, where they arrived in the stadium in a gem encrusted black cab, singing hits such as Wannabe and Spice Up Your Life.

Spectacular show: The girls last performed together at the closing ceremony of the London 2012 Olympics, where they arrived in the stadium in a gem encrusted black cab