Prime Minister Julia Gillard has confirmed she will cut short her visit to the APEC summit in Russia to return home, after learning on Saturday of her father John's death.
Ms Gillard has described her late father as her "inspiration" and says she is shocked by his death.
She says above all, her father taught her to love learning and to understand its power to change lives.
"He always regretted his family background meant he had not proceeded on to higher education as a young man.
"He was determined that I had the opportunities he was denied.
"I will miss him for the rest of my life."
Mr Gillard was 83.
Ms Gillard said she would return home to Adelaide as soon as possible to grieve with her family.
She has asked for her family's privacy to be respected.
Trade Minister Craig Emerson will fill in for her at the APEC summit.
The media was first alerted that something was wrong when Ms Gillard failed to show up for the first session of the APEC summit on Saturday. Dr Emerson appeared in her place.
Russian President Vladimir Putin later announced the news to the conference.
"At the onset of our meeting I would like to say that one of our colleagues, the Australian prime minister, had a very unfortunate tragedy in her family," he said.
"Her father passed away so I would like on behalf of all of us to express condolences to her and members of her family."
John Gillard was a psychiatric nurse and a coal miner during his working life.
The Gillard family moved from Wales to Adelaide in 1966 under the "Ten Pound Pom" scheme for the sake of young Julia's bronchial health.
When his daughter became the first female prime minister of Australia Mr Gillard said the feat had been beyond his "wildest dreams".
Mr Gillard is also survived by his wife Moira and their other daughter Alison.
Earlier on Saturday, Ms Gillard held bilateral meetings with Malaysian Prime Minister Najib Razak and Papua New Guinea Prime Minister Peter O'Neill.
Ms Gillard and Mr O'Neill signed a memorandum of understanding to allow Australia to send asylum seekers to PNG's Manus Island.
She also discussed asylum seekers and other topics with Mr Najib.
The prime minister was to have used the APEC summit to push for an accord to further open up the region's higher education market.
She was also expected to try and shore up support for an agreement that would see APEC's 21 nations slash tariffs on environmental goods to no more than 5 per cent by the year 2015.
She was then to have meet with the leaders of Japan, Peru, New Zealand and Vietnam.
It is expected Dr Emerson will continue to represent her at the summit and on the sidelines.
