Olivia Newton-John has revealed her breast cancer has returned.

Olivia Newton-John has revealed she is battling cancer for the second time.

The Australian singer and actress was forced to postpone her US and Canadian tour dates next month after discovering back pain was actually breast cancer that has metastasised to the sacrum.

That same back pain had earlier caused her to postpone the first half of her tour, before the cancer was discovered.

Olivia Newton-John, Deborah Hutton, Balance by Deborah Hutton
Olivia Newton-John and John Farnham give cancer patients surprise Christmas treat

In a statement on her Facebook page early this morning, Ms Newton-John said she is confident after a short course of photon radiation therapy, she’d “be back later in the year, better than ever”.

“I decided on my direction of therapies after consultation with my doctors and natural therapists and the medical team at my Olivia Newton-John Cancer Wellness and Research Centre in Melbourne, Australia,” she said.

The British-born Australian star first battled breast cancer 25 years ago and has since used her own experience to promote awareness about the disease.

© Nine Digital Pty Ltd 2017

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