The 'Insatiable' hitmaker believes there would need to be a large amount of money for the group, consisting of herself, Kimberley Walsh, Cheryl Cole, Nicola Roberts and Sarah Harding, to get back together.
She said: "It would depend on everybody's feeling. The money that would need to be invested in it is another factor.
"Between the five of us The Hair budget alone was enough to feed a small country. It was through the roof! I think we bought our hairdresser an entire extension on the back of her house on one album campaign. If she wasn't driving a Bentley then she should have been."
The 25-year-old singer also believes Cheryl's solo success and appearance on UK TV talent show 'The X Factor' will dictate when the band will get back together.
She added to i-D magazine: "Cheryl's success is a point for all the rest of us to consider from our own points of view.
"We've got to be realistic about what has happened to Cheryl over the last couple of years."