Andrew Peacock has been remembered as "the most influential opposition leader" who did not become a prime minister at a state memorial service in Melbourne.
Mr Peacock died in April last year at the age of 82 at his home in Austin, Texas.
Prime Minister Scott Morrison, Treasurer Josh Frydenberg, Home Affairs Minister Marise Payne, former Victorian premier Jeff Kennett and former AFL stars James Hird and Sam Newman were among those in attendance at the memorial service held on Friday.
Mr Morrison paid homage to Mr Peacock's warmth and good nature.
"People felt comfortable around Andrew, even if they knew him very little, or knew him greatly," Mr Morrison said.
Mr Morrison said Mr Peacock "dominated the landscape", calling him "the most influential opposition leader [to have never become] prime minister".
Mr Morrison also spoke of the rivalry between Mr Peacock and John Howard.
"Andrew said he and John never stopped talking and that is our instruction, from their experience," he said.
"As iron sharpens iron, so one sharpens another."
Ms Payne paid homage to Mr Peacock's achievements as Minister for Foreign Affairs, highlighting his "essential role in Papua New Guinea's independence".
Mr Peacock visited Papua New Guinea more than fifty times in his career and was awarded the Grand Companion of the Order of Logohu, making him an honorary chief.
"Papua New Guineans were bowled over when he sat with them, shared a beer or a meal and listened rather than lectured," Ms Payne said.
"That was the Andrew Peacock I know and admire so much."
Mr Kennett shared memories of his decades long friendship with Mr Peacock and addressed a private phone call between the two that caused scandals when leaked to the press in 1987.
He linked the anecdote to recent revelations about private text messages, and addressing Mr Morrison in the audience, paid tribute to the strength of Mr Peacock in similar circumstances.
"It is a story, sadly, in terms of private conversations continually being released, Prime Minister. Ours happened 37 years ago. And still people take some pleasure in trying to embarrass those who are the subject of these things," Mr Kennett said.
"I'm sure Andrew would have responded in the same way you have, Prime Minister. That is, to disregard and not to involve themselves in any form of retaliation."
The 'colt from Kooyong'
Peacock was born in Melbourne on February 13, 1939, and elected to parliament at the age of 27.
Dubbed the "colt from Kooyong", he served in federal parliament for more than 28 years and was a minister in the Gorton, McMahon and Fraser governments.
As leader of the Liberal Party, he was defeated by Bob Hawke in the 1984 and 1990 elections.
After leaving parliament in 1994, Mr Peacock served as Australia's ambassador to the United States from 1997 to 1999.
He is survived by his wife Penne and three children.
ABC/AAP