The N-Dubz star stated that her act had come into the music industry at "just the right time" and were certainly capable of fulfilling their goal of becoming as successful as the Spice Girls.
"The girls are going to be the biggest girl band we've had for years," Contostavlos told the Sunday Mirror. "They're coming into the industry just at the right time when there's a big gap in the market for them.
"There's a lot of pressure on them to deliver but they can do it. People are saying they could be as big as the Spice Girls and I really think they could. They want to work their butts off and they're so focused."
Contostavlos went on to describe Little Mix's winner's single 'Cannonball' as a mere "formality" before the band have the chance to carve their own sound.
"If I'm being honest the debut single 'Cannonball' is more of a formality for them," she said. "The real fun will begin when they get in the studio and find their identity. That's when they're going to start the ball rolling."
Little Mix have been tipped to make £8m following their X Factor win.
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