A supporter of the YES campaign eats a sausage cooked on a barbecue that is part of their booth in the center of the Northern Territory capital city of Darwin on Aug 30, 2023. (PHOTO / AFP)

SYDNEY — Support for the inclusion of an Indigenous advisory panel in Australia's constitution has dipped further, a poll showed on Monday, putting the landmark proposal on track for defeat ahead of a national vote next month.

Voters have swung against a "Voice to Parliament" for the fifth month in a row, a survey conducted for the Sydney Morning Herald newspaper showed, as the government struggles to convince sceptical and undecided voters to vote for the proposal.

Support has slid to 43 percent in the latest survey, down from 46 percent in August with voters in New South Wales and Victoria, Australia's most populous states, shifting against the proposal

Australians will vote in the referendum on Oct 14, when they will be asked whether they support altering the constitution to set up an Indigenous committee to advise the federal parliament.

READ MORE: Indigenous Voice referendum in Australia faces misinformation

The referendum requires a national majority of votes as well as a majority of votes in at least four of the six states in order to change the constitution. The survey, however, showed only the island state of Tasmania supported the Voice.

Since Australian independence in 1901, only eight of the 44 proposals for constitutional change have been approved.

Support has slid to 43 percent in the latest survey, down from 46 percent in August with voters in New South Wales and Victoria, Australia's most populous states, shifting against the proposal.

The 'No' vote is strongest in Queensland and Western Australia with 61 percent set to reject the Voice.

The poll also showed the approval ratings for Prime Minister Anthony Albanese, who has staked significant political capital on the referendum, suffering a drop in ratings, falling into negative territory for the first time since the May 2022 election.

The referendum debate has divided opinions with supporters arguing the Voice will bring progress for the Aboriginal community, recognise the 65,000 year-old culture and "unite the nation". Opponents say it would be divisive and hand excessive powers to the body, while others have described it as tokenism and toothless.

READ MORE: Support for Australia’s landmark Indigenous referendum dips

Making up about 3.2 percent of Australia's near 26 million population, the Aboriginal people were marginalised by British colonial rulers and are not mentioned in the 122-year-old constitution.