Seven delegates have stormed out of a national indigenous convention in Uluru to protest against constitutional recognition, stating “we won’t sell out our mob”, but organisers are committed to reaching a united outcome before the summit wraps up.

More than 250 indigenous leaders from across the country have gathered in Central Australia to hammer out what amendments to the founding document might look like, in the largest meeting of its kind in at least a decade.

But seven delegates and about a dozen of their supporters from NSW and Victoria derailed the meeting on Thursday, claiming their calls for a treaty are being diminished in favour of constitutional recognition, which they say is a “sell out”.

Tensions have been building over the past two days amid impassioned and sometimes tense discussions, and NSW Aboriginal elder Jenny Munro criticised what she called a disrespectful process.

“It’s not a dialogue, it’s a one-way conversation. Every time we try and raise an issue our voices are silenced,” she told reporters in Uluru.

“They are not looking at any alternatives options other than the (Cape York leader) Noel Pearson road map. And like Native Title that will prove to be an abject failure.”

Dubbo delegate Fred Hooper believes indigenous Australians should follow their Canadian and New Zealand counterparts in negotiating a treaty for compensation and land reparations.

He says while tokenistic recognition would alleviate white Australia’s guilt, a treaty would achieve real practical benefits for Aboriginal people.

“This could have been a very unique and historical event… in the spiritual heart of the First Nations of Australia. Today I think they’ve divided us,” he said.

Victorian delegate Lydia Thorpe said there’s been a concerted effort to thwart her mandate, which rejects constitutional recognition.

“We don’t need a referendum. We need a sovereign treaty,” she said.

The Referendum Council says it’s still united and committed to reaching “some outcome” when the summit wraps up on Friday.

Co-chair Pat Anderson stressed that most NSW and Victorian delegates are still supporting the process.

“This is a difficult conversation. It’s inevitable that there will be some robust debate,” she said.

“There’s a strong feeling of continuing to finish this task.”

Local Anangu traditional owner Alison Hunt said she was deeply disappointed by what she labelled an unproductive distraction.

“We’ve got to give the government a strong message by tomorrow,” she said.

“We have to be seen as responsible people, speaking together. We might have our differences but by tomorrow we have to speak as one… for our future generations.”

Recommendations are due to be presented to Prime Minister Malcolm Turnbull and Opposition Leader Bill Shorten in late June, with a final proposal to be put to voters.

– AAP