OSCAR-winning actress Nicole Kidman is said to be shocked and "beyond devastated" after the sudden death of her father in Singapore, as fans around the world expressed their condolences and support for her.

Her publicist and friend Leslee Dart told Huffington Post that "Nicole and her family are in shock by the sudden death of her father. She appreciates the outpouring of support and kindly requests privacy during this very difficult time".

Us Weekly, quoting an insider, said the actress was "beside herself" when she learnt of the death of her father Antony Kidman in Singapore on Friday morning local time.

"Keith vowed to be with her as long as he needs to during this horrible time and he is supporting his wife to the fullest. She is beyond devastated and in total shock," the insider said, referring to Kidman's husband, country star Keith Urban.

The Sydney Morning Herald reported that the Hollywood actress arrived at her grieving family's Greenwich home in Sydney's lower north shore on Sunday morning. Her younger sister Antonia reportedly arrived on Saturday morning with two young girls, believed to be her daughters, the Daily Mail reported.

Dr Kidman, a renowned clinical psychologist who was 75, collapsed at the Tanglin Club after his morning exercise. He had been visiting Antonia who lives in Singapore with her husband, a managing director at Scotiabank, and their six children.

Urban has cancelled his shows to support his wife. He was set to be at Washington State Fair on Saturday but announced on Twitter and Facebook that his show has been rescheduled for Sept 19.

He also cancelled his charity performance at Sherwood Country Club in Thousand Oaks, California on Thursday night upon hearing the news, E! News reported. He reportedly rushed to be with his wife at their home in Nashville.

"We are in a deep state of grief at the passing of Nic's father and are heading to Australia to be with family," Urban said in a statement on Facebook. "We want to thank everyone from the bottom of our hearts for their love, prayers and support through this devastating loss."

Fans and friends of the actress have expressed support for her on social media.

"I am so very sorry and I am in tears...Please take care of yourself. I know that you are going to be very upset,'' Alfredo Zotti wrote on Kidman's Facebook page.

"I don't know what to say, I am in shock. I know many psychologists from many corners of the world and Dr Kidman was one of the best. What a lovely man, I will miss him terribly,'' he added.

Jenny Cooney twitted: "Am devasted for #NicoleKidman at the loss of her dad...He was her rock and was always a class act and devoted dad #RIP".

"She was the image of her dad! I'm so sorry for her now. They looked very close and I know what it is to lose a dad to whom I was very close and whom I loved so much. Poor Nicole. RIP her dad,'' another fan Mise tweeted.

Dr Kidman was described as a family man who doted on his two daughters. He and his wife Janelle recently celebrated their 50th wedding anniversary.

He was a director of the Health Psychology Unit at the University of Technology Sydney (UTS). In 2005, he was awarded an Order of Australia for his contributions to health services.

Professor Attila Brungs, vice-chancellor of the university, said in a statement: "It is with great sadness that we learn of Dr Kidman's sudden passing. During his 43 years at the UTS, Tony has contributed greatly - as a colleague, as a researcher, and as a health practitioner.

"Tony will be missed by all at UTS."