Cape York leader Noel Pearson and Arnhem Land powerbroker Galarrwuy Yunupingu said a historic opportunity to unite the nation through constitutional reform would be squandered unless indigenous leaders advocated universal national citizenship over a "treaty" between two sovereign states.
However, symbolic reform of the constitutional preamble should not come at the expense of practical measures to combat endemic Aboriginal disadvantage, the leaders warned.
As the nation edges closer towards a change to the Constitution's preamble to recognise the first Australians, differing images of the form that recognition should take are emerging.
Constitutional recognition would be meaningless unless Australia first became a republic, Mr Yunupingu told The Australian, and, inversely, an Australian republic would be hollow at its core if it did not recognise and confront the devastating realities of colonialism for indigenous cultures.
"Call the republic number one," Mr Yunupingu said. "And then immediately after, call the constitutional reform.
"We are entering a new era which is Australia's own, going away from the Westminster control to a new era."
Mr Yunupingu said the republic and constitutional reform questions were inextricably linked, with the "deliberate injustices" that occurred under British colonisation demanding correction.
"It will be corrected through a republic," Mr Yunupingu said.
"Republic is a vehicle to that correction."
Mr Yunupingu's comments are likely to be met with nervousness in the Aboriginal community, with many believing constitutional recognition for indigenous people should not be mixed up with the republic question, as it was in the failed 1999 referendum.
Mr Pearson told The Australian indigenous leaders must present a model for constitutional reform that was capable of convincing conservatives - "the millions of John Howards in this country" - to vote for constitutional reform at a referendum.
"You (must) explain to them that, no, we are not proposing this as an agreement between two sovereign nations, we are proposing this as an agreement between an indigenous people of the nation and the rest of the country," Mr Pearson said. "Then possibly you might have less opposition and alarm to the concept.
"We have got to achieve two things. One is we have to recognise indigenous people as a distinct people but at the same time we can't fracture the universal national citizenship. We can't create a separate citizenship - (Kevin) Rudd, the parliament, and the nation at large are not talking about a two-tiered citizenship."
The lines of division between indigenous leaders over the constitutional question were drawn at the Prime Minister's 2020 Summit last weekend, with reconciliation patriarch Patrick Dodson injecting renewed energy into the push for a treaty.
Aboriginal academic Marcia Langton - a longtime advocate of constitutional reform to amend Australia's "19th century, racist" constitution - said the treaty question could be settled if Australia embraced the Canadian model, whose constitution retrospectively validated existing and future treaties with indigenous Canadians.
Professor Langton, Melbourne University's professor of Australian indigenous studies, said presenting the republic and constitutional reform issues in one future referendum may prove fatal for indigenous constitutional recognition.
"Constitutional reform will require a referendum, which will require a majority of the states and a majority of the voters," she said.
"And that would be very difficult to achieve given Australia's history of conservatism on constitutional reform."
Professor Langton sparked an angry debate among Aboriginal leaders and activists following the 2020 Summit when she identified a sense of "resistance and denial" among senior indigenous leaders towards the harsh realities within remote Aboriginal communities, such as alcohol, violence and gambling - problems dooming the future of indigenous children.
She told The Australian after the summit that "it was useful for people to feel included in the national conversation again after years of being excluded" but she felt the summit was "a missed opportunity in terms of our most pressing problems, and that is the future of indigenous children".
Mr Pearson, who attended last weekend's 2020 Summit but left early because of illness, said he supported a move for formal constitutional recognition of Aboriginal people but warned that the same old slogans were not going to work.
He agreed with Mr Yunupingu that a practical approach to ending Aboriginal disadvantage should take place alongside a symbolic approach.
"I don't see it as an either-or," he said. "The practical has to go hand in hand with the symbolic and the rights have also got to go hand in hand with the responsibilities.
"The fact that it is now a new situation is a good thing. It doesn't mean that many of the policies of the previous government were wrong and it doesn't automatically mean the previously disengaged voices are completely right ... we stand in a position of good opportunity because of the tectonic shift that the previous government was prepared to grapple with.
"The main practical thrust of the Cape York reforms and the Northern Territory intervention are correct. I don't view them as a mistake we've got to abandon."
Mr Yunupingu flatly rejected the approach of Aborigines achieving settlement with white Australians through a treaty.
"All that is rubbish, it's a dead horse," he said. "It's a word that is nothing but a humbug.
"Treaty doesn't go anywhere - it's a piece of paper, a piece of settlement. If treaty was dealt with with Captain Cook there and then, it would have been a treaty. So I'm not interested - treaty is not my bread and butter, not in today's politics."
Mr Pearson also urged Aborigines to put forward propositions "that have got a chance with the Australian people and the Government of the day".
"What we have is preparedness by the conservatives to consider constitutional amendment, so there's real positive hope there that's got to be built upon," he said.
" Everyone who attended (the summit) would understand that there's huge scepticism about a treaty or an agreement. They should put forward these propositions in a way that is likely to achieve a better reception this time around than last time around. That's my concern."