Former Australian Prime Minister Malcolm Fraser has died at the age of 84.
A statement says Mr Fraser died in the early hours of Friday after a short illness.
"It is with deep sadness that we inform you that after a brief illness John Malcolm Fraser died peacefully in the early hours of the morning of 20 March 2015," the statement from Mr Fraser's office said.
"We appreciate that this will be a shock to all who knew and loved him, but ask that the family be left in peace at this difficult time."
Mr Fraser served as prime minister from November 1975 until 1983.
Treasurer Joe Hockey said Mr Fraser contributed to building a better Australia.
"These events just indicate how in one way or another we all stand on the shoulders of those that were before us," Mr Hockey said on Friday.
"Right or wrong, many people have contributed to public life over a long period of time that have helped to build a better Australia and unquestionably he was one of them. So we pass on our condolences."
Mr Fraser was a prolific user of Twitter.
His last message a day ago linked to an Australian National University website story: "Time for a new China vision - Asia and the Pacific - ANU"
Liberal Party pollster Mark Textor passed on his condolences on Twitter.
"Rest In Peace Malcolm #Fraser. A Man of considerable dignity and rare gravitas."
Senior Labor MP Michelle Rowland tweeted: "Malcolm Fraser provided strong leadership on matters of multiculturalism and racial equality. May he rest in peace."
Greens senator Sarah Hanson-Young said: "Mr Fraser a politician of principle and leader of compassion. A true gentleman with a heart full of empathy. I am devastated."
Another senior Labor MP Matt Thistlethwaite said: "Vale former PM Malcolm Fraser. An admirable defender of human rights who stood by his beliefs."
One of the first tributes to Malcolm Fraser, who has died aged 84, has come from a Labor senator.
Doug Cameron was shocked to hear of Mr Fraser's death on Friday, having only recently dined with the former prime minister and his wife Tamie.
"I am just devastated that Australia has lost a great voice for human rights," Senator Cameron told reporters in Canberra.
- AAP