LINCOLN, Neb. (AP) — A husband and wife who don't want the proposed Keystone XL pipeline to run through their farm have deeded a plot of their land over to a Native American tribe, creating a potential roadblock for the project.

Art and Helen Tanderup signed over a 1.6-acre plot of land to the Ponca Indian Tribe on Sunday. The Ponca enjoy special legal status as a federally recognized tribe.

The land has been used as a planting space for sacred Ponca corn for the last five years, and it was chosen in part because it sits on the $8 billion pipeline's proposed route. It's also part of the historic route that Ponca tribe members were forced to take when the U.S. government relocated them to present-day Oklahoma in 1877.