Leading anti-Voice campaigner Nyunggai Warren Mundine has lashed the Uluru Statement from the Heart as “a symbolic declaration of war”.

In a fiery speech at the National Press Club in Canberra, Mundine also accused the Yes referendum campaign of being “built on a pack of lies”.

“One lie is that Indigenous people don’t currently have a voice. That people aren’t listened to in making laws and policies. It’s the opposite,” he said.

“Indigenous Australians have many voices. Hundreds of Indigenous organisations are immersed in policy-making affecting Indigenous Australians.”

Polling showing a continued decline in support for enshrining an advisory body in the constitution and that the No side maintains a majority of voters has bolstered Mundine’s message ahead of his speech on Tuesday.

“We described the Uluru Statement as a symbolic declaration of war against modern Australia,” he said.

“The canvas is a glossy marketing brochure for the misappropriation of culture, a misrepresentation of history and for a radical and divisive vision of Australia — all done in the name of Indigenous Australians but working against us.”

Mundine repeated his arguments that the Voice is divisive. He said the Uluru Statement “couldn’t be further from the idea of reconciliation”.

“It sees Indigenous Australians as trapped in victimhood and oppression. Not free or able to make their own decisions. Self-determination is an unrealised aspiration. This is a lie. It includes a self-proclaimed history of Indigenous Australia, called Our Story, written to shame Australians about their non-Indigenous ancestors and Australia’s founding,” he said.

“No nation has had a perfect beginning. Most have had bloody and brutal beginnings founded in invasion, conquest, revolution or war. I don’t judge a nation by the worst of its history, but how it seeks to become its better self. And by that measure, I judge Australia well.”

The Voice to Parliament is the culmination of decades of engagement with Aboriginal and Torres Strait people.

It led to the 2017 Uluru Statement from the Heart. The statement, which runs to just over 400 words, outlines what First Nations delegates at the Uluru conference believed should change in Australia for them to be properly recognised.

Leading Yes campaigner and Uluru statement architect Megan Davis described Mundine’s speech as “really disappointing and inflammatory”.

“The Uluru Statement from the Heart was an expression of peace and love to the Australian people, it is about belonging and unifying the nation and I find it really repugnant the notion it could be associated at all with the language of the declaration of war,” she told the ABC.

“It is very disappointing to see the No campaign resort to these kinds of inflammatory comments in a nation that has been grappling with recognition for … years and here we are, three weeks before the ballot box, where we are asking Australians to walk with us in a movement of the Australian people for a better future. That is what the Uluru statement says.”

Davis said polling had shown Australians did not like the “to and fro” of No claims that then had to be rebutted by those in favour of the Voice.

“This is pretty baseline Trumpian misinformation, I think it really tips over into the line of unacceptable political communication,” she said.

In more recent days, Mundine has separated his comments from fellow No campaigner Senator Jacinta Nampijinpa Price, arguing voting against an Indigenous advisory body in the constitution will help progress treaties, something he supports.

Mr Mundine has also advocated for changing Australia Day.

Opposition Leader Peter Dutton has shut down any talk of a treaty.

Australians will vote in the Indigenous Voice referendum on October 14.

-with AAP