Thousands of people have rallied across Australia in support of a campaign to recognize Indigenous peoples in the Constitution. Activists are seeking to shore up the "yes" vote ahead of a referendum on whether to give the country's original inhabitants a say in key policies affecting them.

Sunday's rallies came during the annual week celebrating Aboriginal and Torres Strait Islander culture.

A "yes" vote in the referendum would create a permanent advisory body called the Indigenous Voice to Parliament.

A rally attendee described the campaign as "a great opportunity for all Australians to get behind something that is going to make this country better and particularly for the Indigenous people that deserve it."

Public opinion in Australia has gradually trended in favor of a more empathetic approach to Indigenous affairs and self-determination. But recent opinion polls show the "no" camp closing the gap ahead of the vote to be held later this year.

Indigenous Australians still face disadvantages, including discrimination and poor health and education outcomes.

Prime Minister Anthony Albanese's Labor government backs the change, while the opposition Liberal-National conservatives urge a "no" vote.

Legislation enabling the referendum passed the Parliament last month. It's expected to be held sometime between October and December.