An interim report on a Voice for Indigenous Australians has been handed to the responsible minister after dozens of co-design meetings over more than a year.
Three working groups have met more than 70 times since talks began in October 2019.
The 52 members have developed a range of contested models and options.
The co-design and senior advisory groups have now finalised their proposals and recommendations.
Ray Griggs from the National Indigenous Australians Agency said their interim report captured "robust deliberations" throughout the process.
The report was handed to Indigenous Australians Minister Ken Wyatt on Friday.
"This will mark the completion of the first stage of the process," Mr Griggs told a Senate estimates hearing in Canberra.
Public consultations are expected to run until March and Mr Griggs anticipates a final report will be published between June and August next year.
He said Mr Wyatt wanted to push the process along quickly, but would not be drawn on whether potential legislation would be introduced by the end of next year.
"I don't think I should speak to a legislative timetable but I know the minister is very keen to see this through," Mr Griggs told the committee.
Aboriginal leader Pat Turner, who sits on a senior advisory group providing input on the co-design, recently criticised the process as convoluted and flawed.
Ms Turner warned the proposed voice was doomed to fail unless shortcomings were addressed.
She raised concerns about the government-controlled process being disjointed, conflicted and counterproductive.
The process has been based on advice being given to the government for it to decide on a model.
The government selected its own advisers, Indigenous and non-Indigenous, three separate committees and a senior advisory group.
Terms of reference imposed limits on what participants could discuss.
Individuals were appointed by the government to support the minister rather than representing their constituencies, organisations or cultural groups.
Ms Turner said this compromised the strength of their voices and the chance for Indigenous people to be heard.
She would not accept any model that fell short of the principles outlines in the 2017 Uluru Statement from the Heart.
The statement contained several proposals including a constitutionally-entrenched voice to parliament on laws about Indigenous people.
The coalition government immediately rejected the idea.
The government is instead pursuing an Indigenous voice that will not be enshrined in the constitution and may not be legislated.
Australian Associated Press