POP princess Kylie Minogue has been forced to cancel two concerts scheduled for this week after being diagnosed with a respiratory tract infection.

The singer has pulled the plug on shows in Manchester on Monday and Tuesday, but it is hoped she will have recovered enough to perform later in the week.

A spokesman for the Manchester Evening News arena (MEN), where Kylie was due to perform on her Showgirl Homecoming tour, said doctors had advised the Aussie star not to sing.

The 38-year-old had been due to perform six concerts in Manchester but was forced to pull out half way through the second show on Saturday night.

A statement on the MEN Arena website said the tour party's "worst fears" had come true when the singer herself fell ill.

Her early departure was blamed on a bad bout of flu, which was said to have also hit several other members of her crew.

A spokesman has denied the health scare was linked to her battle with breast cancer, which caused a career hiatus before a comeback tour that began in Sydney, Australia, last November.

Fans with tickets for the two cancelled gigs are advised to hang onto them until a decision is made about whether they will happen at a later date.

Kylie began her career as an actress on the Australian soap Neighbours and has gone on to become one of the most famous pop performers in the world.