Indigenous advocate Noel Pearson says a rejection of the Voice to Parliament would represent a failure of a whole generation of Indigenous leadership, saying it would then be up to a new generation to chart a different way forward.

The respected land rights activist said he would "fall silent" if the nation voted against enshrining an Indigenous advisory body in the constitution. 

The first referendum in decades will be held later this year. 

"That'll be the end of it," Mr Pearson told 7.30.

"I have pursued a middle path, a middle path between the original Australians and the new Australians."

Mr Pearson was asked by host Sarah Ferguson what a failed referendum would mean for him personally. 

"I hope it doesn’t come to that," he said.

"If the advocacy of that pathway fails, well, then a whole generation of leadership will have failed, a whole generation of Indigenous leadership will have failed because we will have advocated coming together in partnership with government and we would have made an invitation to the Australian people that was repudiated.

"I don't think we have anything left after that. It'll be up to a new generation to chart a new course because we will have been rejected."

Campaigners against the Voice have argued the body would do little to improve practical outcomes in the most disadvantaged Indigenous communities. 

But Mr Pearson said engaging directly with communities at "ground zero" was exactly what the Voice was designed to do. 

"It's got to happen in my hometown, it's got to happen in the communities of Cape York, it's got to happen in Alice Springs, it's got to happen in Yuendumu," he said. 

"If nothing happens at ground zero, this Voice will be worthless. It's all about the grassroots." 

Voice was developed under Coalition watch 

The Liberal Party is yet to declare its position on the Voice, while its Coalition partner, the National Party, has resolved to vote no. 

Asked how important it would be to the referendum's success for Opposition Leader Peter Dutton to actively support it, Mr Pearson said: "I think it's very important for Peter to do that."

Mr Pearson pointed out the Voice idea had been "under construction" during periods of Coalition federal government, so it was not an idea that had come "from the left wing". 

Consultation with Indigenous communities had been going on for years in the lead-up to the gathering of Indigenous leaders at Uluru in 2017, where the Statement from the Heart was written. 

Mr Pearson said he was "absolutely appalled" with former prime minister Tony Abbott over his strident opposition to the Voice. 

"He was a very strong advocate for constitutional recognition when he was prime minister," he said.

"I really think that this kind of reflexive opposition that too many like Tony are adopting in relation to this issue is a travesty for the country.

"Now is the time for us to come together."

He said issues like violence and unemployment — often cited by both Mr Dutton and Mr Abbott — could not be solved without the Voice. 

"I work day in, day out in the stony fields of Indigenous disadvantage and struggle. And I can tell you that out of all of the work we do, the most help that we can get to get on top of our problems is to have a Voice to the government and a Voice to the parliament. It's absolutely crucial." 

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