Stars’ sweet messages for Olivia

Olivia Newton-John’s celebrity friends have flocked to wish the singer well after she was diagnosed with breast cancer for the second time.

It was initially thought that the star had sciatica after she was experiencing severe back pain which unfortunately turned out to be her second bout of the disease.

The star has indefinitely postponed her entire U.S. and Canadian tour.

First diagnosed with breast cancer in 1992, Olivia, 68, has previously opened up about surviving the illness more than two decades ago, saying while it was a difficult time in her life, upon reflection it was a "gift".

Olivia’s good friend Tina Arena sent best wishes to her “dear, dear friend” news.com.au reported.

Tina said: “Knowing the kind of woman she is, she turns things around and she is capable of turning this around too. She is a fighter.”

“Australia will rally behind Olivia, the world will rally behind her because she’s loved and that love will make her move forward. That’s what I believe.”

The Chains singer encouraged people to donate to the Olivia Newtown-John Cancer and Wellness Centre in Melbourne to show their support.

Delta Goodrem paid tribute to her idol on Instagram calling Olivia her “hero”.

She wrote: “Sending my deepest love and support to my hero, friend and mentor Olivia as she starts treatment. If there is one person that embodies hope and healing it’s Olivia. She is one of the world’s kindest and most giving humans and I send you all my love & well wishes. Love you so much. All my heart Delta xx”.

Delta herself has battled cancer and also featured on a song with Olivia called Right Here With You with all the proceeds going to the Olivia Newton-John Cancer and Wellness Centre.

The Voice judge recently played Olivia for an upcoming Channel 7 miniseries.

Host Richard Wilkins teared-up when he was announcing the news this morning on the Today Show.

“We send her all our love. She’s a wonderful person. It’s so sad,” he said.

Long-time friend Paul Hogan has also spoken out about the devastating news on Sunrise saying: “It’s a tragedy.”

RELATED: Olivia Newton-John's brave cancer battle
RELATED:Olivia Newton-John opens up on cancer battle

Other stars including singer Molly Meldrum, music act Human Nature and Karl Stefanovic have all sent their well-wishes to the Grease star.

Olivia is set to undergo a range of treatments including photon radiation and other natural wellness therapies and “is confident she will be back later in the year, better than ever, to celebrate her shows.”

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