The Assembly of First Nations (AFN) has passed a resolution calling for Canada's national railways to voluntarily shut down during the group's "day of action" on June 29.

Native chiefs at a special AFN conference almost unanimously adopted the approach Wednesday in Gatineau, Que.

The AFN prefers diplomacy but was pushed to adopt the tougher tactic by those seeking to pressure the government through economic disruptions.

The step serves as a veiled warning to the Canadian National Railway and the Canadian Pacific Railway that they will face disruptions on June 29.

Last week, Manitoba chief Terry Nelson said he'd push to block rail lines to protest slow progress on First Nations land claims.

Nelson said the blockades would start at 4 p.m. on June 29 and go for 24 hours.

"... There are only two ways of dealing with the white man. One, either you pick up a gun, or you stand between the white man and his money," Nelson, of the Roseau River First Nation, told CTV Newsnet's Mike Duffy Live.

"I prefer to stand between the white man and his money. And I think it's pretty darned clear that if I were speaking about the poverty of the First Nations, nobody would even care."

It was Nelson's resolution Tuesday that called for AFN's national executive to ask the railways to shut down. Only one chief voted against the mandate.

AFN Grand Chief Phil Fontaine said there was no push being made for blockades but that a request was being made to the railways. He did not comment on action that would be taken if the railways refused to shut down.

"They've had to shut down in the past, right? They've had to, and we would much prefer that it be done voluntarily," Fontaine said.

Canadian Pacific Railway spokesperson Mark Seland told The Globe and Mail in an email that the company had to discuss the resolution before commenting in detail. However, he did say that CN can't agree to voluntarily shut down operations for a day.

"We can't entertain shutting down any section of our system on a voluntary basis," said Hallman. He said doing so would be irresponsible to both customers and the Canadian economy.

Indian Affairs Minister Jim Prentice also condemned the request saying it was wrong for the AFN to use companies as a bargaining tool with the government.

Fontaine said the AFN's day of action is meant to increase awareness of aboriginal issues and demands for progress on land claims and social funding issues.