The 30-year-old is one of the judges on the new panel of the UK series along with Tulisa Contostavlos, Louis Walsh and Gary Barlow.
Speaking to UK newspaper Daily Mail, she said: 'I am so excited that I have joined The X Factor UK and am able to spend time in one of my favourite places in the world. I can't wait to meet the next superstar!'
She added: 'When I was in Birmingham at the start of June for The X Factor auditions, I wore black 6in Louboutins, a cropped yellow lace top, Lorraine Schwartz diamonds and a black studded skirt by Twenty8Twelve.
'I'm still young, so I can show a bit of midriff, can't I?'