* Aboriginal leaders set to meet prime minister on Friday
* Natives could bring economy "to its knees", says top chief
* Many of Canada's 1.2 million aboriginals live in poverty
By David Ljunggren
OTTAWA, Jan 10 (Reuters) - Native Canadians are so angry that they could resort to blocking resource development and bring the economy "to its knees" unless the Conservative government addresses their grievances, an influential chief said on Thursday.
Native Canadian chiefs are due to meet with Prime Minister Stephen Harper on Friday to discuss the poor living conditions facing many of Canada's 1.2 million aboriginals.
"We have had enough. Our young people have had enough. Our women have had enough ... . We have nothing left to lose," said Grand Chief Derek Nepinak from the province of Manitoba.
Activists have already blockaded some rail lines and threatened to close Canada's borders with the United States in a campaign they call "Idle No More."
Canada has 633 separate native "bands," each of which have their own communities and lands, and not all share the same opinions. The chief of the Assembly of First Nations, the aboriginal umbrella group, said his members had come to a tipping point, but he made no mention of damaging the economy.
"You cannot ignore what is happening with Idle No More... We will drive the final stake in the heart of colonialism and it will happen in this generation," Shawn Atleo told a separate news conference.
"First Nations are not opposed to resource development, they are just not supportive of development at any cost," he said.
Native Canadian leaders say they want more federal money, a greater say over what happens to resources on their land and more respect from the federal Conservative government.
"These are demands, not requests," said Nepinak. "The Idle No More movement has the people - it has the people and the numbers - that can bring the Canadian economy to its knees. It can stop Prime Minister Stephen Harper's resource development plan," Nepinak told reporters in Ottawa.
"We have the warriors that are standing up now, that are willing to go that far. So we're not here to make requests, we're here to demand attention," he said.
Aboriginal bands are unhappy about Enbridge Inc's plans to build a pipeline from the oil sands of Alberta to the Pacific province of British Columbia, and some say they will not allow the project to go ahead.
Some aboriginal bands oppose the Enbridge pipeline on the grounds that it is too environmentally dangerous while others say the company did not do enough to consult them before applying for permission to go ahead with the project.
Nepinak said he wants to extend a "diplomatic hand" toward resolving the issues and gave no details about what he meant by bringing the economy to its knees.
Nepinak and other Manitoba chiefs are also demanding that Ottawa rescind parts of two recent budget acts they say reduce environmental protection for lakes and rivers, and make it easier to sell lands on the reserves where many natives live.
"We've been working tirelessly to gain access through various channels into this Harper regime ... . How do we trust the words of this prime minister?" Nepinak asked.
Successive Canadian governments have struggled for decades to improve the life of aboriginals.
Ottawa spends around C$11 billion ($11.1 billion) a year on its aboriginal population, yet living conditions for many are poor, particularly for those on reserves with high rates of poverty, addiction, joblessness and suicide.
As part of the Idle No More campaign, protesters blocked a Canadian National Railway Co line in Sarnia, Ontario, in late December and early January.