There is an early voting period underway in a landmark referendum on providing Indigenous people with a voice in parliament.

With the reform, Aboriginal and Torres Strait Islander people would be recognised in the country’s constitution and a permanent advisory body would be established for them.

Over the past 50 years, there have been no successful referendums in the country.

While opinion polls showed support for the proposal for a long time, the No side seems to be taking the lead as the vote approaches.

The majority of Australians will vote on 14 October, but those who are unable to do so can vote at select polling centres across the country starting on Tuesday.

In 2017, a historic document called the Uluru Statement from the Heart recommended Voice to Parliament. The statement was drafted by more than 250 Indigenous leaders and is considered the best call to action for reform on issues affecting First Nations Australians. Moreover, it outlines a longer process of making treaties and telling the truth.

Voice’s proposal has been the subject of fierce debate in Australia, as well as misinformation and racist abuse.

Aboriginal and Torres Strait Islander people face lower life expectancy and disproportionately poorer health and education outcomes compared to other Australians, according to its supporters.

Others, however, contend that the Voice is largely symbolic and won’t bring about real change, and that it could undermine Australia’s existing government.

The referendum must be approved by a majority of Australians, as well as by at least four of Australia’s six states.

Parliament would design and debate the composition, functions, and powers of the body, whose advice would not be binding.

According to a poll conducted on Tuesday, Yes supporters are making ground for the first time in months, despite a steady decline in public support for the Voice.

The last time Australia held a referendum was in 1999, when it rejected the opportunity to become a republic.