The Algonquins of Ontario are one step closer to assuming tens of thousands of acres of their ancestral territory in a historic treaty, but their counterparts in Quebec are vowing legal action to stymie the agreement and delay a deal decades in the making.

The agreement-in-principle, signed Tuesday in Ottawa, encompasses roughly 36,000 square kilometres of land stretching from Parliament Hill to parts of Algonquin Park and up to North Bay, an area that Algonquins in Quebec also say is their territory.

"If it's Algonquin territory, then every registered Algonquin should become a beneficiary to any treaty that's happening on our territory," Lance Haymond, the chief of Kebaowek First Nation, said in an interview with CBC News.

"We didn't divide up the Algonquin territory. That was governments many, many years ago, that physically created separation."

Preliminary estimates pegged the number of Algonquin beneficiaries at roughly 8,000, a figure he said should be much higher given their numbers in Quebec.

The cash payment associated with the treaty is currently set at $300 million, although Indigenous leaders are pushing for more.

Ten thousand legitimate Algonquins are going to be excluded from ever benefiting from a final treaty. - Lance Haymond

Haymond said about one million hectares of the land that will be surrendered — when the treaty is finally ratified — actually belongs to the Kebaowek, Timiskaming and Wolf Lake First Nations over the provincial border, and the Algonquins of Ontario alone cannot extinguish that title.

He said he is meeting with his legal team to discuss whether they will file an injunction to try and stop the process altogether or file an Aboriginal title case for the same lands.

The Quebec chief also wants a sit-down with Indigenous Affairs Minister Carolyn Bennett, something he says he was promised in February but so far to no avail. He wants to impress upon her his serious concerns about the territorial overlap, and who her department considers "Algonquin" for the purposes of this treaty process.

"I can't just legitimately sit back and watch that 6,000 non-Aboriginal peoples have voted yes for a land claim, but 10,000 legitimate Algonquins are going to be excluded from ever benefiting from a final treaty."

Algonquin claimants questioned

Haymond's community commissioned a study of the list of eligible voters who voted to ratify the agreement-in-principle with the federal government in March, and found that some had tenuous ancestral connections to the Algonquin nation.

Even Prime Minister Justin Trudeau would qualify under these rules, the chief said.

"At least 60 to 70 per cent of these individuals cannot qualify as being Algonquin," Haymond said. "In fact most of those families have been removed from our nation for 200, 300 years."

The figures are based on genealogical studies by researchers at the Algonquin Nation Secretariat.

The chief said the federal government has created two different standards: first, the rigid process a person has to follow to obtain Indian status — which requires you to show at least three generations of your family have had continual intermarriage with the Algonquin nation — and second, the one set-up for this land claim.

"Someone just has to self-identify, and be able to attach their genealogy to one of the 12 root ancestors part of the process."

Robert Potts, the senior negotiator for the Algonquin claim, pushed back against such criticism Tuesday saying they have followed a rigorous vetting process of their own to determine eligible claimants. He has strenuously denied Haymond's claims.

"I can assure you a tremendous amount of effort and thought is going into this," he said, noting they are consulting with their own genealogical experts and it is being overseen by a judge.

'Willing to take anything'

Kirby Whiteduck, the chief of the Algonquins of Pikwakanagan, the only First Nations band part of the Ontario treaty, said that simply claiming ancestry will not be enough.

"You can't just be of descent," he said in an interview with CBC News.

"If you don't exercise your Aboriginal rights and belong to a collective, you don't necessarily have Aboriginal rights, according to the law, but there are cases of extenuating circumstances that we have to consider."

Kirby Whiteduck, chief of the Algonquins of Pikwakanagan, said he hopes to negotiate improvements to the agreement in principle signed this week. (CBC)

His own community, populated by status Indians, voted against the deal 327 to 256, but the negotiators moved ahead with signing the agreement despite his First Nations' narrow opposition.

"We've had our internal agreements, and our spats, and disagreements with the other negotiating teams, and governments, and it's not as easy at it looks," Whiteduck said.

Ontario, the federal government and the Algonquins of Ontario have been negotiating for 24 years, but the Algonquins have laid claim to the land for more than 250 years — and they say the Crown never extinguished their title to the land.

"Look, they've waited 24 years for a deal, and at this point, you know, they were willing to take anything," Haymond said.