The Saturdays: 'We're irreplaceable'

Saturdays stars Vanessa White and Una Healy have said that all of the group's members are now essential parts of the five-piece.

The girls also told The Sun that their vocal performances are a key factor in the band's success.

Healy said of a recent acoustic performance: "This session really strips it down to show that we're singers.

"We're not a dance group like the Pussycat Dolls - only one or two of them can sing."

White added: "We've always been fighting since we started the group to prove that we're not just a bunch of pretty girls who dance around.

"And we're all irreplaceable. It would be so weird if a new person came in because they wouldn't have the same memories as we have, so it would be hard for them not to feel left out."

Earlier this year, pop rivals Dolly Rockers said that The Saturdays "could have been five completely different girls and nobody would have given a s**t", but singer Lucie Kay later admitted regretting the comments.