TORONTO - Aboriginal people in Ontario are prepared to lay down their lives to protect their traditional lands from any unwanted development, a group of First Nations chiefs said Tuesday.

Five aboriginal chiefs served notice on the Ontario and federal governments, developers and the public that they'll assert their treaty rights over their traditional territory and ancestral lands.

That includes the rights to natural resources — such as fish, trees, mines and water— deriving benefit from those resources and the conditions under which other groups may access or use them, which must be consistent with their traditional laws, said Ontario Regional Chief Stan Beardy.

"All those seeking to access or use First Nations lands and resources have, at a minimum, a duty to engage, enquire and consult with First Nations with the standards of free, prior and informed consent," he said.

"We will take appropriate steps to enforce these assertions."

Tuesday's declaration follows a Supreme Court of Canada ruling in late June which awarded 1,700 square kilometres of territory to British Columbia's Tsilhqot'in First Nation, providing long-awaited clarification on how to prove aboriginal title.

The ruling also formally acknowledged the legitimacy of indigenous land claims to wider territory beyond individual settlement sites.

But in a separate decision a few weeks later, the court upheld the Ontario government's power to permit industrial logging on Grassy Narrows First Nation's traditional lands. Grassy Narrows is different from the Tsilhqot'in decision because it involves treaty land, not aboriginal title.

Grassy Narrows argued that only Ottawa has the power to take up the land because treaty promises were made with the federal Crown.

The high court ruled that the province doesn't need the federal government's permission to allow forestry and mining activity under an 1873 treaty that ceded large swaths of Ontario and Manitoba to the federal government.

The Ontario chiefs who spoke out on Tuesday said the provincial and federal governments haven't respected the agreements their ancestors signed more than a century ago, which gives First Nations the right to assert jurisdiction over lands and resources.

Aboriginal communities have seen what Canadian and Ontario laws have done to their land over the last 147 years, Beardy said.

"The land has become sick," he said. "We become sick. We become poor, desperate and dying."

The people of Grassy Narrows First Nation are still suffering from mercury poisoning decades after the Wabigoon river around their land was contaminated by a local paper mill, he said.

Grand Chief of Treaty #3, Warren White, argued that Prime Minister Stephen Harper recognizes the state of Israel, but not the lands of Canada's aboriginal peoples.

"He needs to have the same principles that he's saying about Israel lands to Treaty 3 territory and native lands in Canada," White said.

"Clean up your own backyard before you go and spill a lot of money into disasters in other countries."

Grand Chief Harvey Yesno of the Nishnawbe Aski Nation added that the province's aboriginal people will draw a line in the stand, put a stake in the ground and tie themselves to it if that's what it takes to protect their land from unwanted resource development.

"We're no longer just going to be civilly disobedient. We're going to defend our lands, and there's a big difference there," he said.

"Our young people are dying, our people are dying. So let's die at least defending our land."

Aboriginal communities don't want to harm others, said Beardy. But they'll do what they must to stop an incursion on their lands, such as forming human blockades to stop the clearcutting of trees, he said.

"Anything that happens on our aboriginal homeland now, they must consult with us," said Roger Fobister Sr., chief of Grassy Narrows First Nation. "Even if they're going to cut down one tree, they better ask us."

Note to readers: This is a corrected story. A previous version said the Supreme Court argued that only Ottawa has the power to take up the land. In fact, the Grassy Narrows First Nation made that argument.

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