Katy Perry to stand in for Dannii Minogue on X Factor

It has not been revealed which city will see Perry join the panel

Pop stars Katy Perry, Pixie Lott and Natalie Imbruglia will appear as guest judges on the next series of the X Factor, ITV1 has announced.

The singers are standing in for regular presenter Dannii Minogue, who is currently expecting a baby.

Geri Halliwell joined Simon Cowell, Louis Walsh and Cheryl Cole at the first round of auditions in Glasgow earlier this week.

More temporary replacements are expected to be announced soon.

Minogue, who is due to give birth in July, will return for the judges' houses stage of the competition later in the year.

According to some reports, Halliwell's appearance in Scotland did not go down well with the live audience.

However, an X Factor spokesperson refused to comment on the crowd's reaction to the former Spice Girl.

Imbruglia will appear at the Birmingham auditions on 13 and 14 June, but dates for the other judges have not yet been announced.

It was also confirmed this week that Konnie Huq would be the new presenter of The Xtra Factor on ITV2.