Indigenous leader Noel Pearson is alleged to have called Malcolm Turnbull a "white c***", Indigenous Minister Ken Wyatt a "black c***" and Indigenous Labor senator Pat Dodson a "f***ing black c***", in what one witness described as an offensive tirade outside the Prime Minister's office.

Key points: The alleged outburst followed a constitutional recognition meeting last year

The alleged outburst followed a constitutional recognition meeting last year At the meeting, Mr Pearson's model for an Indigenous representative body was rejected

At the meeting, Mr Pearson's model for an Indigenous representative body was rejected Mr Pearson denies claims he launched into a tirade at politicians including the PM

Exposing division over progress toward constitutional recognition for Indigenous Australians — an issue thrashed out by stakeholders in Uluru two weeks ago — the alleged outburst, which Mr Pearson denies, followed a meeting of the Referendum Council late last year.

The council, of which Mr Pearson is a member, met on November 25 to discuss progress towards a referendum to recognise Indigenous peoples in the Australian Constitution.

The meeting was also attended by Opposition Leader Bill Shorten, Minister for Indigenous Affairs Nigel Scullion, now Minister for Indigenous Health Ken Wyatt, Senator Patrick Dodson, MP Linda Burney and Senator Malarndirri McCarthy.

The most powerful names in politics and Indigenous affairs gathered in the one room to discuss constitutional recognition for Indigenous Australians.

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Shortly after the meeting ended, discourse allegedly turned into a tirade by Mr Pearson.

An MP who attended the meeting in the PM's office told the ABC "Noel spoke at the beginning of the meeting and at the end" to argue for the inclusion in the constitution of a representative body of Aboriginal people which would "scrutinise legislation to look at its impact on Aboriginal and Torres Strait Islander people".

But Mr Pearson's model was rejected at the meeting as unlikely to be supported by Australians.

After the meeting, in the sitting room of the Prime Minister's office, "there was a fairly lively discussion with the Prime Minister and Noel".

"I heard the Prime Minister say 'I will not insult you, I will listen to your views but I am being pragmatic that your model is highly unlikely to be supported'," the MP said.

'It's the way Noel operates': Warren Entsch

Liberal MP Warren Entsch, a long-time critic of Mr Pearson, was not at the meeting but said he had been told what happened by "witnesses that were there".

"That was enough to trigger him. Noelie [had a] tantrum and called [Turnbull] a white c***," he said.

"Pearson then turned on Senator Patrick Dodson, and Minister Ken Wyatt to call them "black c***s."

Warren Entsch is a long-time critic of Noel Pearson. ( AAP: Mich Tsikas )

Mr Entsch said that was the way Mr Pearson operated.

"It was reported to me by witnesses that were there. And, it's the way Noel operates. But, people make excuses for him all the time," he said.

"Could you imagine what would happen if someone responded in the same disrespectful way to Noel? It would be absolute outrage."

Indigenous Health Minister Ken Wyatt said he witnessed Mr Pearson call Mr Turnbull "an inappropriate set of words that were insulting to the PM".

He refused to elaborate on the exact words or the personal abuse he also allegedly received at the hands of Mr Pearson, saying only that: "The Prime Minister still has to work through constitutional recognition and what I am mindful of, is that Noel is still on that council."

Alleged tirade 'no secret': MP

MP Linda Burney said the alleged tirade was "no secret within political circles".

"I didn't witness it, but I am told by two of the men that were with him [Mr Turnbull] when this happened," she said.

"There is no place in public life for rudeness and abuse."

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Mr Wyatt echoed Ms Burney's sentiments.

"If any Indigenous leader who is an influencer behaves aggressively, it is completely unacceptable and highly inappropriate," he said.

An eyewitness told the ABC that during Mr Pearson's "dummy spit", Mr Pearson said the Aboriginal members of Parliament had "sold out for trinkets" and were no longer fulfilling their obligations to Indigenous Australia.

An adviser to Senator Dodson would not answer questions about Mr Pearson's alleged tirade.

"Constitutional recognition is Senator Dodson's sole focus. He does not want to comment on anything that could jeopardise that," the adviser said.

Political sources told the ABC they believed that Mr Pearson's alleged outburst had been kept quiet by both sides of politics, until now, for fears the story could threaten the progress of constitutional recognition, which was debated at a National Convention last week in Uluru.

As it happens, Mr Pearson's model was chosen as the preferred model of recognition to put to parliament — setting the scene for more fireworks in Canberra.

Noel Pearson is a key member of the Referendum Council. ( Supplied: Referendum Council )

PM's office 'refuse to comment' on alleged outburst

The Prime Minister declined an invitation to attend the closing ceremony of last week's summit. He refused to comment on claims that he had been abused by Mr Pearson.

The PM's spokesperson reiterated by saying: "We refuse to comment."

Mr Pearson declined an interview with the ABC.

"Noel strongly denies the allegations and has referred the matter to his lawyers," his spokesperson said.

Last year, Queensland's Department of Education director-general Jim Watterston claimed in a letter to Mr Pearson that he had abused and intimidated department staff, calling some "arse coverer", "maggot" and "bucket of shit".

Mr Pearson apologised to Mr Watterston.

Also last year, Mr Pearson denied he had abused Queensland Minister for Education Kate Jones, calling her a "f***ing white c***". Ms Jones stands by the claims.

A prominent Indigenous leader who spoke to the ABC on the condition of anonymity said "many eminent Australians hang onto every word that Noel utters".

"When you have an eminent leader who uses language like that when they are challenged, or don't like the response, then that sends a message [to our children] that it is OK. It is OK to call somebody a white 'c' or a black 'c'. Because, if Noel can do it, then it is OK, we can do it."

He believes Mr Pearson's behaviour could have policy implications for Indigenous Australians.

"This is an eminent Indigenous Australian who has shaped some of the thinking [on Indigenous issues in this country]," he said.

"Noel talks of racism and bigotry. You can't talk with a degree of piousness if you yourself are prepared to stoop to using racist terms."