Back in the mid-nineties pop mogul Simon Cowell made what he once called the ‘biggest mistake’ of his career, he didn't sign the Spice Girls. But according to reports, Cowell is now attempting to right the old wrong, by trying to sign the girls for their rumoured reunion tour.

Simon CowellIs Simon Cowell trying to sign a Spice Girls reunion?

The Sun reports that Cowell made an offer to Mel B last week, when he invited her to be a guest judge on the ‘X Factor’. Mel B has always been vocal about wanting to commemorate the band’s 20th anniversary and is said to be one of the three who has said yes to a tour, along with Emma Bunton and Geri Horner.

A backstage source told The Sun: “Simon is desperate to make a new Spice Girls album. He doesn’t want to miss out after the first time around. He spent the auditions last week quizzing Mel about the band and said he would do ‘something mega’ if they signed with him."

More: Mel B Replacing Nicole Scherzinger On 'The X Factor' Auditions

“He kept asking if they were going to be producing new music and said if so, he wants to do it with them. He even went as far as warning Mel that they’d better not talk to any other labels before meeting with him.

“Mel deliberately kept coy and told him they ‘hadn’t finalised everything’, but he wouldn’t leave it alone.” The girls have not yet confirmed if or when the reunion tour will take place, but a new album has also been rumoured.

The story of the Spice Girl’s early history with Cowell has a few differing variations. Mel B once said that the group performed for him in a carpark, but he still turned them down. “Simon was coming out of work and we kind of hijacked the car park he was in and just sang for him,” Mel said.

“We said, ‘Look, we’re going to be famous one day, can you sign us?’ He said, ‘No, it’s not going to work’.” When appearing on ‘American Idol’ in 2009, Victoria said Simon was: "the only man in the music industry who turned down the Spice Girls - and said we would never work."

More: Are The Spice Girls Holding Auditions To Replace Victoria Beckham And Mel C?

But Cowell appears to be under the impression the girls turned him down. When asked by Jay Leno in 2013 what his biggest mistake was, Cowell said: “Spice Girls is probably my biggest mistake."

“You passed on the Spice Girls?” Leno then asked. But Cowell went on to say he did offer them a deal but they didn't accept it. “I knew they were going to be big, but I was just too late on the deal,” he said. “I offered them a deal, but they didn’t want to sign to me, so that kind of hurt at the time.”