Tulisa Contostavlos: 'Little Mix have improved quality of The X Factor groups'

Tulisa Contostavlos is convinced former The X Factor contestants Little Mix have boosted the quality of groups during this year's audition process.

Contostavlos, who mentored the girl band during their time on the show last year, insists the bands hoping to triumph in 2012 have had to work harder to impress the judges since Little Mix were crowned champions.

Speaking ahead of the broadcast of the first auditions this weekend, she says, "The groups this year are great. I think after Little Mix winning last year it's made the groups who have auditioned really up their game. There are also some great solo singers, but at this stage you can never tell who is going to go all the way to the live shows."

And the N-Dubz star is so impressed with her former protegees, she is still working with them in the run-up to the release of their debut album.

She says, "I still see them and they still ask for my advice. I'm more of a behind-the-scenes adviser to them now, as they have their own team doing great things for them."