The Spice Girls have hinted that their sellout reunion tour will travel to Australia early next year, after Mel B made a surprise announcement during the group's final performance at London's Wembley Stadium Saturday evening.

"We'll see you in February in Australia," Mel B told the crowd. Details of live dates in Australia -- which would be the first time the group has performed in the country -- are yet to be officially announced.

However, in a radio interview with Australia's 2Day FM's Grant, Ed and Ash, Mel B admitted the tour isn't locked in.

"You know me by now," she said. "I always say the Spice Girls are going to continue and continue and tour the whole world.

"My thing is, and I've got a bee in my bonnet about it, is that we need to come to Australia first out the gate. I announced it on stage, yes, without everybody else signing off 100 per cent, but I figured if I put it out there maybe it's going to happen."

Ash London said, "So, you're manifesting it?"

"Exactly," Mel B replied.

The singer known as Scary Spice said her bandmates are "not on board fully, yet," with the idea of an Australian tour. "But I will make sure it actually does it happen," she added.

The announcement came at the end of the 13-stop tour, the first tour from the group since 2008 and their first performances since their appearance at the 2012 Summer Olympics closing ceremony.

Mel B's announcement wasn't the only surprise. Geri Horner, aka Ginger Spice, also surprised the crowd Saturday by apologising for quitting the group in 1998.

"I need to say something I should have said a long time ago," she told the 70,000 fans at Wembley.

"I'm sorry. I'm sorry I left. I was just being a brat. It is so good to be back with the girls that I love."

‘I was being a brat’ - Geri apologises for leaving the Spice Girls (in a way that connected with me, at least, more than ever) #spicegirls #spice #geri #icanbeabrattoo pic.twitter.com/0UPnshgC6F

— Jamie Tabberer (@jamietabberer) June 15, 2019

Horner left the group after reportedly suffering from health issues, two years before the whole band went on an indefinite hiatus.

Her emotional announcement came at the end of the Spice Girls' 13-date reunion tour, which also took the group to Dublin, Ireland; Cardiff, Wales; Edinburgh, Scotland; and the English cities of Manchester, Coventry, Sunderland and Bristol.

Horner also shared a heartfelt video of herself standing inside the empty stadium following the final show. "This is it. They are taking it down. It's been amazing," she said, while shrugging her shoulders.

She posted another video thanking her bandmates and everyone who attended the concerts. "Thirteen stadiums. Almost 70,000 people, with three amazing women I've shared that stage with," she said.

"I want to say thank you to Melanie, Melanie and Emma and everybody who showed up for us," Horner said, referring to Melanie Brown (Mel B), Melanie Chisholm and Emma Bunton.

"It has been something that I will never, ever forget. Thank you so much. Big love from Spice World."

A number of high-profile guests attended the concert Saturday, including Grammy award-winning singer Adele.

"Last time I saw the Spice Girls at Wembley was 21 years ago," Adele wrote on Instagram. "Tonight with my nearest and dearest i cried, laughed, screamed, danced, reminisced and fell back in love with my 10 year old self.

"It's no secret how much I love them, how much they inspired me to run for my life and never look back. I finally got to meet Ginger. I got drunk with the girls and quite frankly I can't believe how far I've come."

The Spice Girls launched their reunion tour in May in Dublin, and they performed as a four-piece because Victoria Beckham, aka Posh Spice, declined to take part.