Members of American Indian tribes, indigenous communities and their supporters are demonstrating today in Washington, D.C., calling on the Trump administration to meet with tribal leaders and protesting the construction of the nearly complete Dakota Access Pipeline.The protest is partly led by the Standing Rock Sioux tribe, which has been battling the federal government for more than a year over an oil pipeline that members say endangers their drinking water and has destroyed sacred sites in North Dakota.In drizzling rain and snow, people marched from the headquarters of the U.S. Army Corps of Engineers, which handled route approval for a controversial section of the pipeline just north of the Standing Rock Sioux Reservation, to the White House."They're holding up signs, they're beating drums, they're chanting," NPR's Windsor Johnston reported from the protest site in downtown D.C. Some signs read, "We are here to protect," "water is life" and "stand up to big oil."Lonnie Whitemountain said he's a member of the Standing Rock Sioux tribe and drove 33 hours to take part. "I would tell [President Trump] they need to stop these pipelines that are destroying our water," he said. "He needs to listen to us and realize that he should think about all of our lives.""Honor our treaties," protester Allison Seneguls of Minnesota told Johnston. "We're indigenous to this country, and we should be honored and respected."Some people arrived earlier this week and camped on the National Mall in protest, setting up teepees and other shelters.Eryn Wise is a member of the Jicarilla Apache and Laguna Pueblo tribes of New Mexico and told The Washington Post she spent four months protesting the pipeline in North Dakota."We've never been a part of a movement that represented us in such a powerful and important way. An indigenous-led resistance," the 26-year-old told the newspaper on Friday.According to a website set up by march organizers, the goal of the demonstrations is to highlight the responsibility of the federal government to respect tribal sovereignty.One of the hashtags supporters used on social media was #ConsentNotConsultation, calling on federal agencies to do more than consult with indigenous communities about policies that affect them or their land.Since the Dakota Access Pipeline route near the Standing Rock Sioux Reservation was approved in July 2016, tribal leaders have argued in public statements and court filings that their concerns about the pipeline were not adequately considered by the federal government.The march comes days after the latest legal setback for the Standing Rock Sioux and Cheyenne River Sioux tribes, who are suing the Army Corps and the company building the Dakota Access Pipeline. On Tuesday, a federal judge denied a motion by the tribes to halt final construction of the portion of the pipeline that runs under part of the Missouri River called Lake Oahe.The pipeline company says oil could begin flowing as early as Monday. Copyright 2017 NPR. To see more, visit http://www.npr.org/.