Acknowledging differing opinions within the assembly membership, Atleo, who was sidelined 10 days ago by doctor-ordered sick leave, said he never expected unanimity as the Idle No More protest movement gained momentum.
"We are a diverse people — 52 languages, 633 First Nations — and with this rich diversity comes a wide variety of ideas about how we move forward," Atleo told reporters after being honoured at a meeting of the assembly's B.C. chiefs.
"But make no mistake, on principles of substance, we are unified. We want to see the Crown come meaningfully to the table and address the outstanding treaty relationship."
Atleo, who turned 46 during his brief leave, urged the federal government to take advantage of the opportunity created by the Idle No More movement, which has seen thousands of First Nations take to the streets.
"We also must ensure that we never give any government an excuse to ignore our demands because we're not clear, because our message is confused. We must ensure that we never let governments use division or disunity as an excuse for delay or inaction," said Atleo, who looked tired but said he is feeling well after being laid low with norovirus.
Atleo thanked Attawapiskat Chief Theresa Spence, who just ended a six-week hunger strike, for her "powerful message" and contribution to the movement.
There was speculation about the national chief's role after he announced Jan. 14 he was taking sick leave — days after agreeing to meet with Prime Minister Stephen Harper. Atleo came under fire from some for meeting with Harper in Ottawa.
Chiefs from Manitoba, Ontario and Saskatchewan boycotted the meeting, from which Atleo emerged with a commitment from Harper to further treaty talks in the coming weeks.
Manitoba chiefs, along with some of their counterparts from Ontario, Saskatchewan, Alberta and the Northwest Territories, met behind closed doors earlier this week in Winnipeg.
Derek Nepinak, grand chief of the Assembly of Manitoba Chiefs, said Thursday the chiefs don't want political infighting within the AFN, but have some questions for Atleo.
"Where the challenges present themselves is in the fact that we're working with a Canadian government that wants to speak just with Shawn Atleo ... in a process toward treaty implementation at high levels," Nepinak told reporters.
"Treaties weren't discussed and negotiated at high levels. Treaties were negotiated amongst our people."
Chiefs from the region are planning a special meeting in March in Saskatoon and want Atleo to attend.
"He deserves the opportunity to be heard, to provide clarification for why he went into the Prime Minister's meeting contrary to the wishes of so many chiefs across Canada."
While no decisions were made at the Winnipeg meeting, there was talk of setting up a new national body to deal with treaty rights.
"There had been discussion yesterday that perhaps a new treaty nations alliance may warrant some consideration ... to work towards clearly identifying fundamentals that are based in treaty, as opposed to policy-based fundamentals that really haven't done anything for us for the past 30 years or so," Nepinak said.
The body would not be a rival to the AFN, the chief said, because the AFN has never been tasked with treaty implementation.
In B.C., flanked by leaders of the First Nations Summit, the Union of B.C. Indian Chiefs and the Assembly's NB/PEI Regional Chief Roger Augustine, Atleo agreed it is not his place to negotiate treaty rights but to help open the door.
Grand Chief Stewart Phillip, the president of the Union of B.C. Indian Chiefs known for his outspoken approach to dealing with governments, threw his support behind Atleo.
"We have many different voices saying the same thing: that the status quo is absolutely unacceptable and it's literally killing our people," Phillip said.
"We have an opportunity in front of us and we need to focus on the high-level discussions with the Prime Minister's Office to ensure that this government and all governments are held to account."
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