LONDON (AP) – A respiratory infection has forced Kylie Minogue to cancel two concerts on her comeback tour following treatment for breast cancer.

The Australian singer only managed to perform half of a scheduled 2½-hour concert Saturday in Manchester, northern England, because of the infection, spokesman John Bills said.

On Sunday, a spokesman for the Manchester Evening News arena, where Kylie was performing her Showgirl Homecoming tour, said doctors had advised her to cancel shows Monday and Tuesday.

Bills said there was no connection to Minogue’s recovery from treatment for breast cancer, which led to a year-and-a-half hiatus before a comeback tour that began in Sydney, Australia, in November.

Minogue, 38, was diagnosed with breast cancer in May 2005. She underwent successful surgery in her hometown of Melbourne, Australia, that month, followed by five months of chemotherapy in Paris.