At least one First Nations chief is threatening to launch a widespread blockade of Canadian transportation routes on Saturday if demands for a face-to-face meeting with Prime Minister Stephen Harper and Gov. Gen. David Johnston are not met.

A number of chiefs have said the meeting must happen on their terms: Harper and Johnston must come to a downtown Ottawa hotel for the meeting, and they must both be present at the same time.

If that doesn't happen, Grand Chief Gordon Peters, of the Association of Iroquois and Allied Indians, said a blockade will commence Saturday, shutting down transportation corridors across the country.

First Nations would move to "stop roads, rails, transportation of goods," Peters said, without providing further details of what such a protest would look like. "We just have to walk out on our land and stop it."

Peters' demands are at odds with the proposal already put forward by the federal government and therefore seem unlikely to be met. Harper has already moved up a meeting originally scheduled for Jan. 24, and will sit down for several hours Friday with First Nations leaders who wish to attend the meeting at his office.

Meanwhile, it was announced Thursday that Johnston will hold a ceremonial meeting with native leaders Friday evening, but he has maintained the responsibilities of his office do not include policy decisions or the business of government, meaning he will not participate in talks about treaties.

Those proposals have been deemed unacceptable by some First Nations leaders who have demanded that Johnston, as the representative of the Crown, fully participate in talks which would also involve Harper.

Chief Theresa Spence, who has been on a liquids-only diet since Dec. 11, is among those boycotting the Friday meeting unless both Harper and Johnston are in attendance. Breaking a near-week of silence early Friday, Spence said she will continue her hunger strike until that demand is fulfilled.

The disagreement illustrates the divide within First Nations leaders. While some have vowed to boycott the meeting, others, such as Assembly of First Nations Chief Shawn Atleo, see it as a valuable opportunity to discuss key issues at the highest level.

The threat to launch a Saturday blockade is also divisive. The Mohawks of Kananawake, Que., rejected the call from Peters and other chiefs to block key transportation routes, suggesting they would not take part in such an initiative.

It isn't clear whether the blockade would be a sanctioned Idle No More event. The grassroots movement has been pushing for a renewed relationship between First Nations and the federal government, as well as the resolution of longstanding treaty disagreements, and has spawned dozens of demonstrations across the country and elsewhere.

However, leaders of the movement have intentionally remained separate from any political organization, including Indian bands -- even going so far as to complain that chiefs were taking ownership of Idle No More events by urging their people to attend.

Some have also suggested the so-far peaceful movement could increase in intensity if demands are not met.

With files from The Canadian Press