Indigenous leaders will present an anti-Keystone XL pipeline petition to President Barack Obama on Friday, the latest development in a story The Tyee first began reporting from a South Dakota tribal casino last September.

The move comes only weeks after the State Department announced it would delay a decision on the project by up to 13 months. Some indigenous leaders, particularly those on the Great Plains, fear that even with a reroute, TransCanada's project could still someday damage the Missouri River watershed, among other concerns.

They plan to address the President directly during the White House's annual Tribal Nations Conference, when representatives from more than 565 American tribes meet with top U.S. government officials.

"We strongly believe that the proposed Keystone XL tar sands pipeline is not in the national interest of the United States or Canada," reads their "Mother Earth Accord".

The Tyee was on the scene this September when indigenous leaders from both Canada and the U.S. Great Plains drafted that document in the basement of a tribal casino.

Since then, it's been endorsed by both the National Congress of American Indians (the most influential indigenous lobby group in Washington, DC) and Canada's Assembly of First Nations.

Green activist Bill McKibben, a key organizer in the environmental fight against Keystone XL, praised the Accord on Wednesday.

"It’s a strong document, full of details about the impacts of tar sands mining and pipeline leaks and carbon emissions," he wrote. "But it also speaks with the real power of the people who’ve lived longest and best on this continent."

Geoff Dembicki reports on energy and climate issues for The Tyee.